OutputDebugString Checker is a software tool that scans source code looking for calls to OutputDebugString() that are not conditionally compiled. Reasons to look for OutputDebugString(): 1) Leaving these calls in your program slows down execution. The method to communicate the string to a debugger is by raising an exception. This is slow, and if a debugger is monitoring the exception, it’s slower than without the debugger. 2) Leaving these calls in your program allows data to leak out of your program. The contents of these calls many contain function names, debugging information, data the program is processing. Do you want your customers to see this information?