SxS does not support configuration namespace in app.config files

If the configuration namespace is referenced in an app.config, you may receive the following error messages in the system event log:


  • Syntax error in manifest or policy file file name on line 2. The manifest file root element must be assembly.

  • The application failed to launch because of an invalid manifest.

  • Generate Activation Context failed for file name.Manifest. Reference error message: The operation completed successfully.


You may also receive this message box:


  • The operation could not be completed. This application has failed to start because the application configuration is incorrect. Reinstalling the application may fix this problem.


If you were using a beta version of Visual Studio 2005, you may have the configuration namespace, http://schemas.microsoft.com/.NetConfiguration/v2.0, referenced in your app.config. This is not supported by SxS, so you application will fail to load when you create an application manifest, or attempt to use ClickOnce.

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