During the mess I had on my Vista system because of the faulty memory chip, I has many blue screen errors, some DEP errors, and an amusing COM+ Error. I say "amusing" because there is apparently an assertion left in the final vista build (assertions get generally removed from shipping code), telling me the source code file and  line of the error. This includes the full path of the Vista source used to build the system! Here it goes:

The COM+ Event System detected a bad return code during its 
internal processing. HRESULT was 8007043c from line 45 of 

      d:\vistartm\com\complus\src\events\tier1\eventsystemobj.cpp.
      
Please contact Microsoft Product Support Services to report this error.

Funny...