NFS Windows 7

hi

i have in my enterprise EMC ISILON

i installed on 3 pcs windows 7 ultimate in order to add the NFS protocol.

when i cut and paste a file DATA to ARCHIVE, it made immediately from MAC.

but on pc with windows 7, i see the copy window and on it, it is writing CALCUL...during a long time and i can't cancel it

so, do you have a resolution because normally, the cut and paste it's very quickly.

thanks