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MSCORLIB.PDB not available?

Apr 7, 2009 at 11:47 AM
What am I doing wrong?
1) The latest version I have of MSCORLIB.dll is in: C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727
2) The module loaded information (see below) suggests this is the version of the DLL my program is loading
3) Cannot manually or automatically retrieve the symbol file using -d or -f options. NetMassDownloader indicates the mscorlib.pdb is NOT available, but the BLOG says it is!


From a loaded module viewer for my VS9 project captured during debug session:

C:\WINDOWS\ASSEMBLY\NATIVEIMAGES_V2.0.50727_32\MSCORLIB\6D667F19D687361886990F3CA0F49816\MSCORLIB.NI.DLL 2.0.50727.3082 (QFE.050727-3000) 11486720 March 31, 2009 19:50:25 Microsoft Common Language Runtime Class Library Microsoft® .NET Framework 2.0.50727.3082

Version Info:
VS 9.0.21022.8 RTM
.NET v3.5 SP1
XP Pro v5.1.2600  sp3

Apr 7, 2009 at 3:16 PM

Problem resolved! I will recite my mistakes below in hopes that someone as ignorant as me will be helped by this information. The information below pertains to your VS server loading. I could not determine why NetMassDownloader could not find MSCORLIB symbol file, but at least I've got what I need.

Originally, I believe, I had followed older instructions that only included "Configuring Visual Studio for Debugging", which, according to these instructions alone, should have sufficed. However, I later found a reference to another source server,, which did cause the symbols for MSCORLIB to be loaded. Finally, I noticed that you CAN actually download this stuff at:, which is referenced in document: Unfortunately, I never saw these instructions because I started my endeavor with an older set of instructions, which are pretty much the same as that found at:

After the source download Setup is finished, VS/options/debugging/symbols will contain another entry (if it has not already been added by user) that points to the install location for the "reference source" installed on your local machine (e.g. c:\documents\<user>\referencesource ). It places this 'new' entry at the end of the list of "Symbol file locations".

Now, if you did what I did, you already had a different directory assigned to the "Cache Symbols" (VS/options/debugging/symbols), which raises a question: "Why didn't the download source setup use the symbol cache as the default in the first place?" If I have understood everything that has taken place, you now have a copy of at least one of the MS Source Servers on your local machine? If so, I would think you should move your "local server" (e.g. c:\documents\<user>\referencesource ) to the top of this list so it begins loading what it can find locally first, instead of checking the web first. I haven't played with altering the server and cache assignments yet, but I will. Right now, I am just happy to have this and other missing symbol files.