Visual Studio 2012 no longer debugs unmanaged C ++

Recently my Visual Studio 2012 lost the ability to debug unmanaged code. I have a C # project that references a C ++ COM module. It uses interop library which I created with tlbimp.exe. The COM module is registered, and the C # project has "Allow native code debugging". I am using Windows 7 (current for updates) as my operating system and this project is set to x86 for C # and C ++. This is a practice I've been doing for years and debugging has never been a problem.

When the project is loaded, the breakpoints are disabled with the message "Currently the breakpoint will not be removed. No symbols have been loaded for this document." When I load the Modules window, the COM module is not listed and I cannot find how to add it ...

Is there a recent update or something that might be causing this issue? What can I do to make this work again?