I'm running NW 6.5 sp4a, and I've had this problem for quite a while.
Certain files if I attempt to rename, I can't. Even if I put the a new
file down, I can't do it. I can delete it, rename it local and then
copy, but not rename it.

I get a message "antivirus" from the server, but I've even unloaded
netshield. It's a bogus error.

If I try and rename a file, I get a message like what follows

Message from server NPV1:
Received Friday, February 10, 2006 9:43:23 AM:

NPV1/DISK1:\npv\IT\soft\drivers\hp systems\dc7600\SP31684.exe - antivirus

It's not local AV either..