See if Server Optimization in RFCB Caching mskb #126026 may help.

>We are doing some testing on different platforms, and installed NT 4.0 on a couple of our new PCs. We are occasionally getting some strange file-related errors. For example, a couple times when packing a table we get a "File Access is Denied" error, and the original table is gone. From this example, and a couple other problem areas, it seems that there must be some kind of OS disk caching going on. It looks like that right after a file is deleted, it still appears to be there for a split second. I wrote two simple test programs, one in VFP 6 and one in VB 6. They basically do the same thing: In a loop, create a file, copy it to a second file, delete the first file, and rename the second file to the first's name. In both test programs, I get errors from time-to-time, sometimes the file copy fails because it can't see or access the first file, and sometimes the rename fails because it doesn't think the first file has been deleted yet. The VB program was normally failing about
>80-100% of the time. I put in a slight delay (about 1/10 of a second), and it appears to work all the time. If I take out the delay, and go to the System Control Panel applet and set the Performance -> Application Performance Boost to "None", it also appears to work all the time. (I've put my test VFP program at the end of this message.)
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>Does anyone know of any inherent problems with NT on newer, faster computers?
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