Permission denied on object sp_sdidebug.txt

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An exception of type 'System.Data.SqlClient.SqlException' occurred in System.Data.dll but was not handled in user code

Additional information: EXECUTE permission denied on object 'sp_sdidebug', database 'master', owner 'dbo'.
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A quick bit of googling reveals that this isn't a uncommon but it's related to SQL debugging and I wasn't attempting to do that. None of my VS projects had 'Enable SQL Debugging' checked. Fortunately the solution was quite straightforward : when attaching the aspnet_wp.exe process to VS, make sure you are only attach managed code.

Click Tools > Attach to Process
Click the Select button just above the list of available processes to attach to
Select 'Debug these code types' and check only the boxes for Managed (and Native i fnecessary) code.
Click OK
Click Attach
Debug as normal


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Once we got this error in a Windows Service, reinstalling it solved the problem.