We have a problem when users try to save spreadsheets to a network drive they
get a error message "The disk is full" but the drive has over 30gb of free
space. If they save the spreadsheet to their desktop they can then copy into
a network location.

The problem appears to be intermitent and has appeared on multiple computers
with multiple spreadsheets.

A few of the computers (but not all which is strange) have several events
created in the event log. In the system log they get,

"The description for Event ID ( 50 ) in Source ( Mup ) cannot be found. The
local computer may not have the necessary registry information or message DLL
files to display messages from a remote computer. You may be able to use the
/AUXSOURCE= flag to retrieve this description; see Help and Support for
details. The following information is part of the event:
\Device\WinDfs\Y:0000000000067318, \Device\WinDfs\Y:000000 .. t\manufact."

Source MUP

Any ideas?