Hmm... Are these local files? I think that you are probably seeing an IO bottleneck but I would need to study the Perfmon logs to get a better idea - which I am willing to do. Do you need help in choosing the counters? Jacob, I haven't forgotten my promise to help and I will try to get that done in the next 24 hours. It has been a bit hectic lately. Mark From: George Bell Sent: Friday, July 25, 2008 5:07 PM To: program-l@xxxxxxxxxxxxx Subject: [program-l] MS Process Monitor + Fast IO disallowed I'm trying to resolve some performance issues with our SAGE Line 50 accounting system. Having installed Microsoft's Process Monitor on my Vista Ultimate system, I can see that during something as mundane as an Invoice date sort, FAST IO DISALLOWED appears. There doesn't seem to be much practical advice around for determining what might turn FAST IO on or off. Some say it could be malware, others that it could be virus checkers and such like. (We do run McAfee here) FWIW, I'm running a Windows Enterprise Server 2003, a plain vanilla Windows Server 2003, one Vista Ultimate workstation, and the rest are XP workstations. Has anybody any thoughts, because I've already lost my part-time bookkeeper due his frustrations over performance? George.