renaming or moving sometimes works only at 2nd try

[mael]

strange
at my first tests switch off the virus scanner didn't change anything
now i had the problem again and i switched it off and the problem was gone

still Unlocker showed only TC as accessing app

it's Gdata Antivirenkit 2005

[djet]

In my case no resident file scanners are active..

[frenky]

Maybe you have some sort of indexing service (ms or e.g. google desktop search or similar) active?

You could also try to turn off windows tooltips (a big maybe....)?

Btw, thanks Clo for an answer, i missed it before, but this did not make any difference in my case.
I tracked my issue to some third party sw that likes to access files, read it in background (idle process) then it does something with it (god know what), stops what ever it is doing if any other activity is noticed, but fails to unlock the file untill it finishes...