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,, 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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