Programs failing to save to AFP share on OS X server 10.4.6

Hi, I am getting a strange problem with OS X Server 10.4.6, running on a G4 Xserve 1Ghz. When working on files in Microsoft Word X and 2004 after having the file open for a few minutes if you try and save we get an error "Word failed reading from this file", or "Bad network connection". Also in Quark 6.52 and Quark 6.1 when trying to save a file to the server we get "File not found [-43]". It is possible to open files, and it is also possible to move files onto the share using finder without any problems. To work on documents we are having to work on them locally on the desktop then copy across once done. The only thing that i can think has changed is the power went off last night, which casued the Xserve to restart. These problems are occuring across all client computers so i am assuming it can only be a problem with the server. Does anyone have any idea what this could be, or any tests that i can do to detmine what is up with it Many Thanks Tim Pearson