When adding two or more counters to the perfmon.exe application (32 bit version) and the counters comes from a remote 64 bit machine (Windows 2008 64 bit) the perfmon.exe application becomes highly unstable, stalls for minutes, misses data samples etc. To repate the problem follow these steps. 1. Start the 32 bit version of the perfmon.exe application on your workstation (any OS will do, Windows XP / 7 , 32 bit or 64 bit) 2. Open the performance register of a remote 64 bit Windows 2008 server (or later) 3. Add two or more counters from that remote server, any counter will do. 4. Watch as the perfmon.exe application will stall/hang for minutes Do it exist a hotfix for this or have Microsoft even acknowledge that this is a serious problem ? To me it looks like its some sort of deadlock on the remote registry server, when one or more calls are made from more then one thread on the calling machine, the remote machine locks up and returns ERROR_BUSY.