In the Source window, you may not be able to obtain a source view of an object if the current code being executed is not part of your program. (For example, you may have halted execution while in a DLL that does not contain debug information.) Check the object name that appears at the top of the Source window. If you do not recognize this name as an object of your own executable, you are probably debugging system code used by, but not compiled with, your program. If you have access to the source code for this object, you could recompile it with debug information so that you can obtain a source view of it.