Debugging: No Locals, Breakpoint not being hit, etc in Visual Studio

Problem: sometimes, VS has trouble seeing Locals for optimized assemblies. Also, even with symbols loaded for a module, a breakpoint is not hit. Or you attach to the w3wp.exe process only to not see your module as loaded (and you know it is).

Solution: say your assembly is My.dll

1. Create a file called My.ini
2. Put this content into that file:

[.Net Framework Debugging Control]
AllowOptimize=0
GenerateTrackingInfo=1

3. Copy the .ini file to the location of the assembly in the GAC