TeamSite slow and copying files to Y drive give error when completed.

System

My users have been copying files through a mapped drive to our TS server. Yesterday they reported that it was very slow and that they were receiving the following error, "Cannot copy xxxxx: the specified network name is no longer valid". The file will copy, but tends to hang the open explorer window on their desktop and takes at least a minute to start. Copying to a local drive on the server works fine without these issues.

I have restarted the entire server and also ran iwfsch -d which found no errors.

I also did an RDP session to the server and copied a local file to the Y: drive and was very slow to start, but eventually copied. It was a small file, under 1 MB.

I have a support case open, but since this is production does anyone have any suggestions while I wait for a reply back?