Opening Office files on a MAC G4 server from a W2K client

[Jason Smith]

I have several W2K machines that are running SP3 that
access various office files on a Macintosh G4 server.
The W2K machines have been added to the MAC LAN and are
utilizing mapped drives to the G4 server. Some of the
W2K machines have no problems accessing, opening, and
saving files on the G4 server. However, some of them
receive errors when attempting to access the various
office files on the G4 server.

Here is an example:

Trying to open an Excel file on the G4 server from the
W2K client, receive the following error:

Excel cannot open or save any more documents because
there is not enough available memory...

I cannot find any configuration differences between the
W2K machines that can open the files on the G4 server and
those that cannot open the files.

Any suggestions as to what could be causing this problem?

Thanks.
..