knod of the head to sfraser, for reminding me that you need to also initialize processInfoRec with the size of the process record.

xpcom/components/nsRepository.cpp

@@ -1490,6 +1490,7 @@ nsresult nsRepository::AutoRegister(NSRegistrationInstant when,
 	    // initialize ProcessInfoRec before calling GetProcessInformation() or die horribly.
 		pInfo.processName = nil;
 		pInfo.processAppSpec = &tempSpec;
+		pInfo.processInfoLength = sizeof(ProcessInfoRec);
 		if (!(err = GetProcessInformation(&psn, &pInfo)))
 		{
 			appFSSpec = *(pInfo.processAppSpec);

xpcom/src/nsRepository.cpp

@@ -1490,6 +1490,7 @@ nsresult nsRepository::AutoRegister(NSRegistrationInstant when,
 	    // initialize ProcessInfoRec before calling GetProcessInformation() or die horribly.
 		pInfo.processName = nil;
 		pInfo.processAppSpec = &tempSpec;
+		pInfo.processInfoLength = sizeof(ProcessInfoRec);
 		if (!(err = GetProcessInformation(&psn, &pInfo)))
 		{
 			appFSSpec = *(pInfo.processAppSpec);