This weekend we installed two new OES2015 severs

We moved our volumes from the old OES11SP1 servers to the new OES2015 servers.

Everything works fine , browsing the volumes goes fine from novell clients.

But now we got complains that sometimes office files are hanging on downloading. Then explorer freezes. If you wait 2 minutes the pc start responding again. Then open the same file again you can open it.

This can't be normal , is this known?