Troubleshooting Office Solution Security
This topic contains tips for solving common problems that you might encounter when you work with securing Office solutions.
Applies to: The information in this topic applies to document-level projects and VSTO add-in projects. See Features Available by Office Application and Project Type.
Users cannot install a solution from a web location if the web site is listed in the Internet Explorer restricted sites zone. This is true even if the solution is signed with a trusted certificate.
The URL of the deployment manifest can be categorized into one of five zones:
If the location of the deployment manifest has been assigned to the restricted sites zone, Visual Studio Tools for Office runtime does not install the solution. If the location is known and can be trusted, the user can remove the location from the restricted sites zone and install the solution. For information about how to manage zones, see Configuring ClickOnce Trusted Publishers.
Internet Explorer Enhanced Security Configuration (IEESC) in Windows Server 2003 and higher, and Internet Explorer 7 and higher, significantly restricts the ability of users to browse the Internet. When users try to install Office solutions from a network file share or web location, they might get the following error message: "Customized functionality in this application will not work because the certificate used to sign the deployment manifest for SolutionName is not trusted. Contact your administrator for further assistance."
With IEESC and Internet Explorer 7 and higher, if the URL of the deployment manifest is categorized in the Internet zone, the manifest must have a certificate from a trusted publisher or the solution cannot be installed. Without IEESC, the default behavior is to prompt the end user to make a trust decision.
To manage the effect of IEESC and Internet Explorer 7 and higher, identify web sites and universal naming convention (UNC) paths that you trust and add them to one of the trusted security zones (Local intranet or Trusted sites).For information about how to manage zones, see Configuring ClickOnce Trusted Publishers.