How to determine which versions of the .NET Framework are installed and whether service packs have been applied

This article describes how to determine which versions of the Microsoft .NET Framework are installed. This article also helps you determine whether any .NET Framework service packs are installed.

For more information about service packs for the .NET Framework 1.0, click the following article number to view the article in the Microsoft Knowledge Base: The Microsoft Update service updates installed versions of the .NET Framework. To make sure that the computer is always up to date, turn on Automatic Updates in Control Panel.

Versions of the .NET Framework

The released versions of the .NET Framework have the following version information.

.NET Framework version	Revision	Version
3.5	Original release	3.5.21022.8
3.5	Service Pack 1	3.5.30729.1
3.0	Original release	3.0.4506.30
3.0	Service Pack 1	3.0.4506.648
3.0	Service Pack 2	3.0.4506.2152
2.0	Original release	2.0.50727.42
2.0	Service Pack 1	2.0.50727.1433
2.0	Service Pack 2	2.0.50727.3053
1.1	Original release	1.1.4322.573
1.1	Service Pack 1	1.1.4322.2032
1.1	Service Pack 1 (Windows Server 2003 32-bit version*)	1.1.4322.2300
1.0	Original release	1.0.3705.0
1.0	Service Pack 1	1.0.3705.209
1.0	Service Pack 2	1.0.3705.288
1.0	Service Pack 3	1.0.3705.6018

*The Microsoft .NET Framework 1.1 is included with the 32-bit version of Windows Server 2003.

Note This information should be used as a general guide for determining which versions of the .NET Framework are installed on a computer. Be aware that files that have a later version number may be files that were included in a hotfix or a hotfix rollup package. These versions are outside the scope of this article.

How to determine which versions of the .NET Framework are installed

To determine which versions of the .NET Framework are installed, locate the %systemroot%\Microsoft.NET\Framework folder. To open this folder, you can paste this address into a Windows Explorer address bar. The following folders contain the released versions of the .NET Framework:

• v3.5
• v3.0
• v2.0.50727
• v1.1.4322
• v1.0.3705

Note If you see other folders that have a vN.N.NXXXX format, they may contain beta versions or pre-released versions of the .NET Framework. Those versions are outside the scope of this article.

To determine which versions of the .NET Framework are installed on a computer, follow these steps:

1. Open any one of the folders in the previous list.
2. Right-click the Mscorlib.dll file, and then click Properties.
3. Click the Version tab, and then note the file version.
4. Use the previous list to determine which version of the .NET Framework is installed on the computer, and then click OK.

Repeat these steps for each version of the .NET Framework on the computer.

How to troubleshoot a .NET Framework installation

For more information about how to troubleshoot a .NET Framework installation, click the following article numbers to view the articles in the Microsoft Knowledge Base:

For more information about the benefits of the .NET Framework, click the following article number to view the article in the Microsoft Knowledge Base: For more information about different configurations of the .NET Framework 1.1, click the following article number to view the article in the Microsoft Knowledge Base: For more information about file versions for the .NET Framework 2.0, the .NET Framework 1.1, and the .NET Framework 1.0, visit the following Microsoft Web site: For Visual C++ sample code that programmatically detects the .NET Framework 1.1, the .NET Framework 1.0, and the .NET Framework service packs, visit the following Microsoft Developer Network (MSDN) Web site: For more information about which .NET Framework version numbers correspond to which service pack, visit the following MSDN Web site: