The debugger correlates code addresses to source code locations by way of symbol files (with PDB
extension). When you install VC++ or a SP for it, the symbols for the CRT (and other VC libraries)
are normally installed in the symbols\dll folder under your Windows installation directory (such as
C:\WINDOWS\). In Visual Studio, you tell the debugger where to find symbols in the Tools | Options
| Debugging | Symbols property page. Make sure you have the updated PDB files in the symbols\dll
directory, and make sure that directory is also listed on the Symbols property page.
Additionally, I would recommend that you add these to your Symbols property page list (after the
Also, I suggest you create a folder on your local hard drive (with lots of free space) to be a local
cache for downloaded Microsoft symbols. Indicate that folder in the edit box indicated below the
Post by void *p;
Prior to loading SP1 for VS 2008, I was able to step into the CRT source.
After loading SP1, the debugger complains that "There is no source code
available for the current location."
I verified this by loading VS 2008 and later SP1 on a clean machine.