Mac Connection Problem

I have a Mac user that is connecting to Novell through Samba. The Mac OS is 10.5.8. The user has recently had problems saving and opening files on the home directory. It seems that it mostly pertains to Office Files. We can pull up jpeg and pdf fine. The problem seems to be intermittent. We have other users on Mac’s that connect through Samba with same OS and seem to have no problems. I had the user even try a different Mac that he has at home and gets the same problem. I looked in the system log and seems like it tries to reestablish connection through Samba to the Novell server when trying to access Office files. It seems we do not get that problem when trying to open other file types. The error that appears when trying to access a *.xls file from the drive is “Microsoft Excel cannot open or save any more documents because there is not enough available memory or disk space.”