Debugging VSTO Using Log Files or Alerts
VSTO isn’t functioning as expected and I need to debug it conveniently

Visual Studio Tools for Office can write all errors that occur during startup to a log file or display each error in a message box. To enable or disable this logging, the user needs to adjust two Windows environment variables.

Managing Environment Variables

Any user can add, modify, or remove a user environment variable. The changes are written to the registry, and are usually effective immediately. However, after a change to user environment variables is made, any open software programs should be restarted to force them to read the new registry values.

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For information about setting environment variables in Microsoft Windows XP, see "How To Manage Environment Variables in Windows XP"


Displaying VSTO Alert Prompts

To display each error in a message box, set the VSTO_SUPPRESSDISPLAYALERTS variable to 0 (zero). You can suppress the messages by setting the variable to 1 (one).

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Logging VSTO Alerts to a Log file

To write the errors to a log file, set the VSTO_LOGALERTS variable to 1 (one).

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Visual Studio Tools for Office creates the log file in the folder that contains the application manifest. The default name is .manifest.log. To stop logging errors, set the variable to 0 (zero).

Last updated 5/3/2011