When you debug .net applications you will sometimes get error messages in windbg. Here are a few of the ones I most commonly get questions around...
Failed to start stack walk
If you run the sos command !clrstack to display the .net stack on a thread, and this thread is a .net thread but it is not currently running any .net code, sos will spit out Failed to start stack walk: 80004005. This does not mean that there is anything wrong with the process or with the debugger. It simply means that sos can't display the stack because there is none.
OS Thread Id: 0x1ec (12)
Failed to start stack walk: 80004005
Unable to walk the managed stack
If you run !clrstack on a native thread (i.e. a thread that has no corresponding System.Threading.Thread), sos will display the following message instead.
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