1. System Requirements for Installing .NET Framework 3.0

Installation drive

When you start the .NET Framework 3.0 installer, the default installation location is on your system drive, which is the drive that boots your system. Please ensure that the required amount of space (up to 500 MB) is available on your system drive.

Copyright Information

• Portions of International CorrectSpell™ spelling correction system © 1993 by Lernout & Hauspie Speech Products N.V. All rights reserved.
• The American Heritage® Dictionary of the English Language, Third Edition Copyright © 1992 Houghton Mifflin Company. Electronic version licensed from Lernout & Hauspie Speech Products N.V. All rights reserved.

2. .NET Framework 3.0: Installation Known Issues

2.1 Download failure when downloading and installing .NET Framework 3.0.

The download and installation of a .NET Framework 3.0 intermittently fails.

To resolve this issue

Rerun dotnetfx3setup.exe from the Web site and try the download again. Click here for more troubleshooting information about download errors.

– or –

Install the full redistributable package dotnetfx3.exe (x86) or dotnetfx3_x64.exe (x64). You can find these redistributable packages on the .NET Framework 3.0 download location.

2.2 Antivirus applications that are configured to clean the Temp folder will cause setup to fail if setup needs to reboot.

If setup needs to reboot, and the antivirus application is set to clean the Temp directory on launch, necessary setup files will be deleted and setup will fail with a program-not-found error.

To resolve this issue

Change your antivirus applications configuration to not clean the Temp folder on launch or reboot before running .NET Framework 3.0 setup. Consult your antivirus documentation for the steps to accomplish this.

2.3 Launching Maintenance Mode from Add or Remove Programs can take several minutes and might give the appearance that setup has failed.

If you have other processes running when you launch Maintenance Mode, such as virus-scanning software, these processes can slow setup considerably and give the appearance that setup has failed.

To resolve this issue

Be patient. There is no workaround. Setup has not failed.

  2.4 No Add Remove Programs entry to uninstall Windows Workflow Foundation.

You may get the "Please uninstall Windows Workflow Foundation" error when installing .NET Framework 3.0 , but there is no ARP entry for Windows Workflow Foundation to uninstall the product.

To resolve this issue

Run the uninstall tool for pre-release version at: http://www.microsoft.com/downloads/details.aspx?FamilyId=AAE7FC63-D405-4E13-909F-E85AA9E66146

2.5 .NET Framework 3.0 installation may overwrite the localized version of MSXML6

On Windows XP SP2 and Windows 2003 SP1, if you have a localized version of MSXML6 previously installed, .NET Framework 3.0 installation will overwrite the localized MXSML6 with the English version.

To resolve this issue

Reinstall the localized version of MSXML6 after installing .NET Framework 3.0 .

2.6 Installation error when installing .NET Framework 3.0  packages on Vista

Windows Vista comes with .NET Framework 3.0. There is no separate installation package required. The standalone .NET Framework 3.0 packages are not supported on Vista. 

2.7 Possible issues when upgrading from a pre-release version of the .NET Framework 3.0 (previously WinFX 3.0)

This section describes issues you may encounter if you previously installed a pre-release (CTP and Beta) version of the .NET Framework 3.0 and want to remove it to upgrade to the RTM version.

To uninstall .NET Framework 3.0, please uninstall through Add and Remove Program (ARP) in the Control Panel. If uninstalling from ARP does not solve the issue, you can review the following:

Run the Uninstall Tool
The .NET Framework 3.0 Uninstall Tool available is available at http://www.microsoft.com/downloads/details.aspx?FamilyId=AAE7FC63-D405-4E13-909F-E85AA9E66146. This tool resolves many uninstall problems and is the best first step in attempting to resolve uninstall/reinstall problems. Details on the correct use of the tool are listed on the download page.

If you cannot run the tool or if it does not resolve your issue, review the Known Issues and Workarounds section below for potential solutions.

Note: These install issues occur only if you have installed an early pre-release version of the .NET Framework 3.0 on your system before installing the RTM version. The issues that cause these behaviors have been addressed in recent .NET Framework 3.0 pre-release editions.

Known Issues and Workarounds

2.7.1“Microsoft Digital Identity Service” (idsvc) is not deleted on uninstall

On uninstall, some pre-release versions of the .NET Framework 3.0 did not correctly delete all services they created. The presence of one of these services on a system blocks the installation of the .NET Framework 3.0. The installation will fail with this error:
ERROR_INSTALL_FAILURE 1603 Fatal error during installation
Also, one of the %temp%\dd_wcf_retCA*.txt log files will show the following:

ServiceModelReg [15:48:08:041]: Installing: Microsoft Digital Identity Service (idsvc)
ServiceModelReg [15:48:08:073]: Error: System.ComponentModel.Win32Exception: The name is already in use as either a service name or a service display name 

To resolve this issue

Run the uninstall tool at: http://www.microsoft.com/downloads/details.aspx?FamilyId=AAE7FC63-D405-4E13-909F-E85AA9E66146

If the issue persists:
Open a command prompt.

1. Click Start.
2. Click All Programs.
3. Click Accessories.
4. Click Command Prompt.
5. In the command prompt, type:
   sc delete “InfoCard Service”
6. Reboot the machine.
7. Restart the .NET Framework 3.0 installation.

2.7.2 Some WCF perf counter registry keys are not deleted on uninstall of some pre-release versions of the .NET Framework 3.0

Some pre-release versions of the .NET Framework 3.0 did not remove all perf counter registry keys on uninstall. The presence of these keys blocks the installation of the .NET Framework 3.0. The installation fails with this error:
                “ERROR_INSTALL_FAILURE 1603 Fatal error during installation”
The following keys may still exist in the registry after uninstall:

• HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSDTC Bridge 3.0.0.0\Performance
• HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ServiceModelEndpoint 3.0.0.0\Performance
• HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ServiceModelOperation 3.0.0.0\Performance
• HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ServiceModelService 3.0.0.0\Performance
• HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SMSvcHost 3.0.0.0\Performance

To resolve this issue

Run the uninstall tool at: http://www.microsoft.com/downloads/details.aspx?FamilyId=AAE7FC63-D405-4E13-909F-E85AA9E66146

If the issue persists, try rebooting. Many issues can destabilize the performance counters. Rebooting can fix some of those issues and is safer than manually editing the registry. If that does not solve the problem, check the following registry keys. Delete the parent registry keys of any of the following that are empty or whose values contain “Wbem*”:

• HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSDTC Bridge 3.0.0.0\Performance
• HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ServiceModelEndpoint 3.0.0.0\Performance
• HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ServiceModelOperation 3.0.0.0\Performance
• HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ServiceModelService 3.0.0.0\Performance
• HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SMSvcHost 3.0.0.0\Performance

For example, if this key is empty:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ServiceModelEndpoint 3.0.0.0\Performance

you should delete:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ServiceModelEndpoint 3.0.0.0”

2.7.3 Stale machine.config entries that reference “2.0.0.0” versions of .NET Framework 3.0 assemblies block installation

Some pre-release versions of the .NET Framework 3.0 did not remove all machine.config entries on uninstall. Any entries that reference the 2.0.0.0 version of “System.ServiceModel.dll” in the machine.config file will block the installation of the .NET Framework 3.0. The installation fails with this error:
        “ERROR_INSTALL_FAILURE 1603 Fatal error during installation”
In addition:

1. An error event appears in the application event log that references problems running ServiceModelReg.exe.
2. The setup log file titled “dd_wcf_retCA*” in the user’s %temp% directory location contains an entry that indicates problems running ServiceModelReg.exe.
3. Either the event log entry or the setup log entry may have an exception similar to the following (time stamp will vary):
   ServiceModelReg [16:21:10:656]: Error: System.IO.FileLoadException: Could not load file or assembly 'System.ServiceModel, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)

To resolve this issue

Remove the stale machine.config entries by hand:

1. From a command window, run “notepad %windir%\microsoft.net\framework\v2.0.50727\config\machine.config”
2. Remove any XML nodes and child nodes that reference System.ServiceModel.dll.
3. If you are running on a 64-bit machine and the following config file exists:
   “%windir%\Microsoft.NET\Framework64\v2.0.50727\config\machine.config”
   edit the file to remove any xml nodes and child nodes that reference System.ServiceModel.dll.

2.7.4 May not be able to web host WCF services if a pre-RC1 version of WCF was previously installed

If you installed a previous version of the .NET Framework 3.0 while IIS was installed, when you upgrade to the RTM version of the .NET Framework 3.0 you may have difficulty accessing WCF services that are IIS hosted using .svc files. On computers running Windows Server 2003, accessing an .svc extension from the browser may return a “404: Page Not Found” error. On computers running Windows XP, the .svc content may be displayed as plain text.

This is due to an issue with WCF script map registrations in a previous release.   

To resolve this issue

There are three ways to work around this issue:

1. Download the unsupported tool, CleanIISScriptMaps.exe from http://wcf.netfx3.com/files/folders/product_team/entry5648.aspx. Run the tool from a command console without any arguments.
2. Uninstall and reinstall IIS or re-create your Web sites:
   1. Uninstall IIS and reinstall it so that the IIS Metabase is refreshed. Then run the WCF install tool manually to re-register the WCF scriptmaps:
      “%windir%\Microsoft.NET\Framework\v3.0\Windows Communication Foundation\ServiceModelReg.exe” /r /y
   2. If you are running Windows 2003 Server, you may be able to resolve the problem by deleting the “Default Web Site” and re-creating it.
3. Install .svc manually as a temporary workaround:
   You can run the following command to install .svc mapping manually. However, this refreshes the IIS Metabase for existing sites. "%windir%\Microsoft.NET\Framework\v3.0\Windows Communication Foundation\ServiceModelReg.exe" /s:W3SVC

2.7.5 IIS metabase corruption blocks installation of the .NET Framework 3.0

If you installed a previous version of the .NET Framework 3.0 while IIS was installed, it’s possible that the IIS metabase was corrupted. This may block the installation of the .NET Framework 3.0.
You can identify this issue in the following ways:

1. The installation fails with this error:
   “ERROR_INSTALL_FAILURE 1603 Fatal error during installation”
2. An error event appears in the application event log that references a failure to register WCF scriptmaps. The source of the event is System.ServiceModel.Install.dll 3.0.0.0.
3. The setup logs in your %temp% directory will also contain references to a failure to register WCF scriptmaps.
4. Either the event log or the setup log may contain the following exception stack trace:
   System.ApplicationException: ServiceModelReg.exe has detected a possible corruption in the IIS metabase that prevents the registration of the ServiceModel IIS scriptmaps. Please either fix the IIS metabase corruption, or, if you do not desire ServiceModel WebHost functionality, disable the IISAdmin service and reregister ServiceModel.

To resolve this issue

1. Uninstall IIS.
2. Re-install IIS.
3. Re-run the .NET Framework 3.0 setup.

3. Troubleshooting Steps for Download Errors

3.1 Background Intelligent Transfer Service (BITS) disabled

This error occurs when the BITS service is disabled, does not exist, has been deleted from the services application, was stopped while download was in progress, or if any service that BITS depends on failed or was deleted. The error message for this problem is "BITS service must be enabled before you start the installation process. Enable the BITS service and run setup again."

To resolve this issue

1. On the Start menu, clickRun.
2. In the Run Dialog box, type services.msc and then click OK.
3. In the list of services, right-click Background Intelligent Transfer Service, and then clickProperties.

   Note: If you do not see Background Intelligent Transfer Service in the list, the service is not installed on your computer. You can download and install BITS from http://www.microsoft.com/downloads/details.aspx?FamilyId=B93356B1-BA43-480F-983D-EB19368F9047.

4. In the Startup type list, selectManual and then click OK.

If these steps do not resolve the problem, you may need to enable the services that BITS depends on.

To enable dependencies

1. Follow steps 1-3 listed above.
2. In the Background Intelligent Transfer Service Properties dialog box, click the Dependencies tab.
3. For each service listed under This service depends on the following system components, follow steps 3 and 4 listed above to enable the service.

3.2 Configuration Errors

These errors occur when BITS interfaces are not registered or the registry settings are corrupted.

To resolve this issue

Upgrade to BITS 2.0 from http://www.microsoft.com/downloads/details.aspx?FamilyId=B93356B1-BA43-480F-983D-EB19368F9047.

– or –

Repair the BITS service by running the bitsadmin tool from the command prompt:
Bitsadmin /util /repairservice /force

You can download the Bitsadmin tool from http://www.microsoft.com/downloads/details.aspx?familyid=49AE8576-9BB9-4126-9761-BA8011FABF38.

3.3 Network Errors

These errors can occur for one or more of the following reasons:

• Unable to reach download server
• URL not found on the server
• Server is overloaded
• Bad gateway or proxy
• Network is disconnected
• Proxy does not support HTTP 1.1

To resolve this issue

Provide correct settings for the proxy server and ensure that your machine is able to correctly resolve the proxy server.

– or –

Upgrade to BITS 2.0. You can download BITS 2.0 from
http://www.microsoft.com/downloads/details.aspx?familyid=49AE8576-9BB9-4126-9761-BA8011FABF38.

Note    To resolve these errors, exit setup, verify that you are connected to the network, and launch setup again.

3.4 Disk Errors

These errors occur when the BITS service failed to create or write to a file. Another program, such as chkdsk.exe, might be running and may have locked the disk and prevented BITS from writing to the file.

To resolve this issue

Make sure that no other program (for example, chkdsk.exe) that could lock the disk is running and retry the download.

– or –

Restart your computer and then launch setup again. Make sure that you are connected to the Internet.

3.5 Proxy Errors

The BITS service failed because of one of the following proxy-related errors:

• The proxy settings are not valid.
• The proxy server requires authentication.
• The computer is not able to resolve the proxy server.

To resolve this issue

Provide correct credentials for the proxy server authentication and restart setup again.

– or –

Upgrade the proxy server to support HTTP 1.1 and ensure that the proxy supports implicit credentials (like NTLM). You may need to contact your network administrator.

– or –

Bypass the proxy by changing your Internet Explorer proxy settings.

To bypass a proxy server:

1. In Internet Explorer, click Tools and then click Internet Options.
2. Click the Connections tab and then clickLAN Settings.
3. Under Proxy server, unselect Use a proxy server for your LAN (these settings will not apply to dial-up or VPN connections) and then clickOK.
4. Click OK again.

If you need further assistance with your proxy server settings, contact your network administrator.

3.6 Other Errors

The BITS service does not run in:

• Safe-boot mode.
• On Windows 2000 from a remote desktop connection.
• When setup is installed by a "run as" command.

To resolve this issue

There is no workaround. These scenarios are not supported.

4. Windows Communication Foundation (WCF) Known Issues

4.1 Windows hotfix is required on Windows XP and Windows Server 2003 to use WS-AtomicTransaction and COM+ Integration functionality

The WCF WS-AtomicTransaction support and COM+ Integration functionality require a Windows hotfix (QFE) in order to work on Windows XP and Windows Server 2003. You can install the hotfix package from http://go.microsoft.com/fwlink/?linkid=46976.

4.2 Managed C++ code generated using SvcUtil.exe tool may not compile

You can use the SvcUtil.exe tool to generate code for Web service proxies and data types from metadata. However, there are known issues with the C++ code provider in Visual Studio 2005 and the .NET Framework 2.0 SDK that can cause the tool to generate Managed C++ code that may not compile. These issues with the C++ code provider will be addressed in a future release of Visual Studio 2005.

4.3 Code generation language support in SvcUtil.exe

SvcUtil.exe can generate code for Web service proxies and data types from metadata in any language that has a managed code provider. SvcUtil has been tested with the C#, VB, and C++ managed code providers. Other code providers have not been tested and may generate code that does not compile or may be otherwise unusable.

4.4 Sending a message to a web-hosted queued service fails when QueueTransferProtocol is set to “Srmp” or “SecureSrmp”

Queues used by Web hosted services contain “.SVC” in their names to map them to the appropriate WCF services. If you install WCF activation features before you install MSMQ HTTP support, an issue with the MSMQ HTTP setup causes .SVC handler mappings to be copied to the MSMQ vdir. Sending an SRMP message to such a queue will then fail as a result.

There are two ways to work around this issue:

1. Install MSMQ HTTP support before installing the WCF activation features.

Or:

1. Delete the .SVC handler mappings from the MSMQ vdir using the IIS management console.
2. Then update the site’s .SVC mappings using:
   “%windir%\Microsoft.NET\Framework\v3.0\Windows Communication Foundation\SMConfigInstaller.exe” /c:install /f:http.
   Note: Use the Framework64 path on 64-bit machines

4.5 Queued channels do not produce full end-to-end traces

There is currently no end-to-end support for tracing messages between MSMQ and WCF queued channels. This is a known issue.

To work around this issue, manually correlate the messages traced in WCF and MSMQ using the MSMQ message ID. This ID is traced in both WCF and MSMQ.

4.6 Known issues when using WMI with NetMsmqBinding and MsmqIntegrationBinding

When you use WMI to inspect the properties of MsmqTransportBindingElement and MsmqIntegrationBindingElement, the enumeration values of ReceiveErrorHandling and QueueTransferProtocol appear as numbers instead of their actual values. This is a known issue. To work around the issue, inspect the configuration for the actual value set for the binding.

When you use WMI to inspect MsmqTransportBindingElement, the MsmqTransportSecurity and TransactedReceiveEnabled properties are missing. This is a known issue.

When you use WMI to inspect MsmqIntegrationTransportBindingElement, the MsmqTransportSecurity, TargetSerializationTypes, and TransactedReceiveEnabled properties are missing. This is a known issue.

4.7 Message dropped errors are logged as message rejected on Windows Vista

When using either the NetMsmqBinding or MsmqIntegrationBinding with WCF queued channels on MSMQ v4 (Windows Vista), dropped message traces are incorrectly logged as rejected messages. This is a known issue.

4.8 Windows Event Viewer displays client identity incorrectly when using an Arabic language certificate for client authentication

When using a local machine certificate [CN=شقشلهش,] for client authentication on an Arabic Windows client, a known issue with Windows Event Viewer causes the client identity to appear incorrectly in the Event Log auditing entry:

ClientIdentity: CN=شقشلهش; 14FDBABD77EA825C391CEC4F830859F72B56009F

In the above example, the string “14” is part of the certificate thumbprint but appears before the certificate subject name.

4.9 IIS Metabase corruption can block installation of the .NET Framework 3.0

If you installed a previous version of the .NET Framework 3.0 while IIS was installed, it’s possible that IIS metabase corruption may block the installation of the .NET Framework 3.0.

You can identify this issue in the following ways:

1. The installation fails with this error:
   “ERROR_INSTALL_FAILURE 1603 Fatal error during installation”
2. An error event appears in the application event log that references a failure to register WCF scriptmaps. The source of the event is System.ServiceModel.Install.dll 3.0.0.0.
3. The setup logs in your %temp% directory will also contain references to a failure to register WCF scriptmaps
4. Either the event log or the setup log may contain the following error message:
   System.ApplicationException: ServiceModelReg.exe has detected a possible corruption in the IIS metabase that prevents the registration of the ServiceModel IIS scriptmaps. Please either fix the IIS metabase corruption, or, if you do not want ServiceModel WebHost functionality, disable the IISAdmin service and reregister ServiceModel.

To resolve this issue:

1. Uninstall IIS.
2. Re-install IIS.
3. Re-run .NET Framework 3.0 setup.

4.10 Exception when running a TCP service and TCP MEX on the same port

When port sharing is enabled, configuring a TCP service and a TCP MEX endpoint to use the same port causes an AddressAlreadyInUse exception when starting the service.

There are two ways to work around this issue:

1. Change the configuration of the TCP service and TCP MEX endpoints to use different ports.
2. Enable port sharing for the TcpTransportBindingElement of the TCP MEX endpoint. The following code illustrates this process:

   ServiceMetadataBehavior mexBehavior = new ServiceMetadataBehavior();
host.Description.Behaviors.Add(mexBehavior);
Binding mexBinding = MetadataExchangeBindings.CreateMexTcpBinding();
CustomBinding mexBinding2 = new CustomBinding(mexBinding);
mexBinding2.Elements.Find<TcpTransportBindingElement>().PortSharingEnabled = true;
host.AddServiceEndpoint(typeof(IMetadataExchange), mexBinding2, mexAddress);

4.11 Fault Messages > 64 KB can cause a ProtocolException

When MaxBufferSize is at least Int.MaxValue – 1024 bytes (2147482623 bytes), sending a fault message larger than 64 KB causes the client to receive a ProtocolException instead of a FaultException. For buffered transfers, MaxBufferSize is the same as MaxReceivedMessageSize. This only affects services using an HTTP(S) transport.

To work around this problem, set the MaxBufferSize (MaxReceivedMessageSize) to Int.MaxValue – 1025 bytes (2147482622 bytes) or smaller. Alternatively, you can directly set HttpWebRequest.DefaultMaximumErrorResponseLength to the desired limit. Setting DefaultMaximumErrorResponseLength will affect all channels in the same application domain.

4.12 Can’t use EncryptBeforeSign and XmlSerializerFormatAttribute on the same contract

Message security with EncryptBeforeSign protection order does not work properly if XmlSerializerFormatAttribute is used on the contract. If both are used, WCF creates messages with invalid body content after decryption—an additional <?xml ..> processing instruction is generated before the first body element.

To avoid this issue, don’t use EncryptBeforeSign with XmlSerializerFormatAttribute on the same contract.

4.13 Can’t host WS-ReliableMessaging Channels using different versions of WS-Addressing

An AppDomain cannot host WS-ReliableMessaging channels that use different versions of WS-Addressing. In such scenarios, the first active channel will dictate the version of WS-Addressing Action headers for all subsequent protocol messages, even if those messages were sent by a channel configured to use a different version of the addressing protocol.

If you need a single application or service to create WS-ReliableMessaging channels that use different WS-Addressing versions, use a separate AppDomain for each of them. When a WCF service is WebHosted, you’ll need to use two virtual directories—one that hosts services with WS-Addressing 1.0 endpoints and one with WS-Addressing August 2004 endpoints.

4.14 WCF event log messages and shell tool tips not localized on certain localized versions of Windows

On Windows XP SP2 or Windows Server 2003 SP1 localized operating systems only, Windows CardSpace and WCF event log messages and CardSpace UI Tool Tips are not localized. This is not an issue on MUI installations.

To work around this issue, perform the following steps:

1. Copy the localized version of icardres.dll.mui to the system32 directory.
   • For example, on a German localized system, copy:
     [windir]\system32\mui\0407\icardres.dll.mui
     to
     [windir]\system32\icardres.dll.mui
2. Copy the localized version of ServiceModelEvents.dll.mui to the Windows Communication Foundation directory.
   For example, on a German localized system, copy:
   [windir]\Microsoft.NET\Framework\v3.0\Windows Communication Foundation\mui\0407\ServiceModelEvents.dll.mui
   to
   [windir]\Microsoft.NET\Framework\v3.0\Windows Communication Foundation\ServiceModelEvents.dll.mui

The localized files replace the English versions of the files in the target directories. If you later repair or uninstall/reinstall WCF you must repeat the previous steps.

4.15 Installation error when installing WCF Optional Component on Windows Vista

There is a known issue when installing the optional Windows Vista component "Microsoft .NET Framework 3.0/Windows Communication Foundation Non-HTTP Activation." If you try to install this component at the same time as any other optional components that require a machine reboot, none of the selected components will be installed.

To avoid this issue, always install the "Microsoft .NET Framework 3.0/Windows Communication Foundation Non-HTTP Activation" component separately.

5. Windows Workflow Foundation Known Issues

5.1 Workflow Web service hosting in Internet Information Services (IIS) 7.0 Integrated Mode

The web.config file generated by the Workflow Project System is compatible with IIS 6.0 hosting. However, IIS 7.0, which ships with Windows Vista, supports execution of the ASP.NET pipeline in two modes: ISAPI Mode (IIS 6.0 Compatible mode) and Integrated Mode. To take advantage of the new Integrated Mode functionality, the web.config file must be modified to look like the following:

<system.webServer>     <modules>         <add name="WorkflowHost" type="System.Workflow.Runtime.Hosting.WorkflowWebHostingModule, System.Workflow.Runtime, Version=3.0.00000.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" preCondition="runtimeVersionv2.0" />     </modules> </system.webServer>

5.2 ExternalDataExchangeService should not be used across multiple workflow runtime instances

You cannot add an ExternalDataExchangeService service to multiple WorkflowRuntime instances. Anytime a new WorkflowRuntime instance is created, a new ExternalDataExchangeService service should be created and any local communication services should be added to the ExternalDataExchangeService service again.

5.3 Static methods added as event handlers are not serialized correctly

When you add a static method as an event handler, it is serialized as this.Method instead of ClassName.Method.

5.4 Compensation fails when the TargetActivityName of a CompensateActivity is a custom composite activity

If you create a custom composite activity containing a child activity that implements ICompensatable and a CompensateActivity activity that compensates the composite activity, but not the child activity explicitly, then compensation will fail with exceptions if the custom activity is placed in a workflow.

To avoid this issue, you should encapsulate all child activities of a custom activity in a CompensatableSequenceActivity activity and implement compensation on that CompensatableSequenceActivity activity.

6. Windows Presentation Foundation Known Issues

6.1 Known issue with the Windows Presentation Foundation build system for solutions with multiple projects and project dependencies

If a solution has multiple projects, then the project directories need to be peers to each other. If you change the project structure such that one project has its root under another project’s directory, you may see unexpected markup compilation errors during Rebuild complaining that a type in a referenced DLL (from one of the dependent projects) could not be found.

Workarounds are:

1. change the directory hierarchies for the projects in the solution, making individual project directories peers to each other OR
2. when faced with this issue: Clean, then Build or Rebuild.