I recently upgraded a VS 2003 C# Windows class library project to VS 2005 and every time try to debug I get the following error:

 System.Data.SqlClient.SqlException: EXECUTE permission denied on object 'sp_sdidebug', database 'master', owner 'dbo'.

I have read that this can be caused by enabling SQL Server Debugging.  Well I check my project settings, and that option is definitely unchecked.  I don't want to debug any sql, just my C# code.

Perhaps this is a conversion issue?? 

I figured out what was happening.  I should have thought of this earlier ...

This class library is the codebehind library for an ASP .Net app.  I started the debugger by attaching to the asp.net worker process and by default VS enabled T-SQL debugging.  I tried attaching again, but this time unchecking all but managed code, and it worked no problem.
 

 Brilliant!  Thank you so much John, I looked for hours after a working solution but none of the Microsoft people seemed to have it and none of the other forum threads but you rock!  : )

How nice it would be if Visual Studio could give a nicer error message. 

I'm glad I could be of assistance!