Cannot find or open the PDB file - PDB not built with DLL

Question

My Visual Studio 2013 ASP.NET webform application has 3 DLL assemblies. When debugging, DLLs and PDBs are created in the same Temporary ASP.NET Files directory for only two of the three DLLs (the Project/VB module and a C# module. The third DLL is also a C# module, and the PDB is not being generated to the same directory as the DLL.

The symbols for that last problem module are not being found. When I attempt to load the symbol files manually selecting a PDB that was created on the same Date/Time as the DLL, I get the error "A matching symbol file was not found in this folder."

Why would PDBs be built in the DLL's directory for two modules and not for the third module? I've tried a variety of options on the Symbol Settings dialog, changing the Symbol file locations and cashe directory, cleaning and rebuilding the solution, and the results are not changed.

Answer 1

Did you check in the advanced build dialog (in your project properties(the one where the pdb is missing) and then, debug info : pdbonly or full ? it must not be set to "none"

Answer 2

This problem was resolved. The C# module that was not producing a symbol file was an old copy of the DLL. Attempts to rebuild the module did not replace the old DLL.

All copies of that old DLL were deleted first and then the module was rebuilt. The next debug attempt showed a new DLL and PDB file were properly created.