Outlook add-in logging

I recently inherited support of an Outlook plugin (add-in) and needed to output a few more debugging statements. I put those lines into the code, but not events were logged into the Event Viewer Application Log as expected. Fumbling around I saw this: https://msdn.microsoft.com/en-us/library/ms269003.aspx?f=255&MSPPError=-2147217396 and added an environment variable VSTO_SUPPRESSDISPLAYALERTS = 0.

Error codes

Just some notes to myself on some resources to help decipher error codes that I often come across. These are sometimes mentioned in the ULS logs with something like hresult= or hr=

• ErrCo.de - awesome and searchable set of error codes on pretty much everything
• Win32 Error Codes
• MS-ERREF
• Description of HRESULT