Well you say the application was written in Visual Basic but then also say C++ ? Unless part of the code was C++ and rolled into the overall
VB program, the chances of finding the answer are slim? If you had the program source code which ever language it is I could take a look at it as I taught both languages for many years. Generally what will happen is an operating system level DLL or other code module will get updated and the program can not interact with it correctly. Possibly someone did an update (you ?) and that would have to be undone.
A final thought, can you post a screen snapshot of the error message box and also one of the Windows task manager to show what is running at the time of the crash? Finally do you know if anything else was running or just started when the crash occurs?