>Defrag on the server (don't know exactly what tool was used, but it took about 4 hrs) did not have any impact.

Well, the defragging was a good idea even if it didn't help MODI FORM - if it takes 4 hours, that usually means there was serious fragmentation, and there may be some small server performance gains that are noticeable.

>It looks that I was wrong about the number of files in dir being a factor, but the files being open on another WS is a factor - see my answer to Thomas message #781623.

Didn't try that yet. I'll test my busy DE form next week with this situation, and see what I find.