>>Without addressing your question, the real answer is for the backup process to notify users that have files open 2 minutes or so before it kills their connections - or, failing that, send a broadcast message to all w/s that may be running and logged in. That lets interactive users shut down gracefully; non-interactive or unattended processes will still get killed ungracefully - but that's no different from what's happening now.
>
>The problem is, no one is addressing my question. Everyone has advice on how to change the backup process, which I don't own. I need to know about the possibility of data corruption when the plug is pulled on an open file that is idle.

OK, I'll address the question somewhat...

I think there is some chance that you WILL lose data. Working late, I'd ASSUME that you are working on something (i.e. changing some 'data' somewhere).
Now thinking of editing a Word document or a .PRG, the file on the HD (local or networked) goes UNtouched while you are editing. Then you save it.
You may be given an option to save it elsewhere. But if you do, you now have the problem of remembering to put it where it actually belongs the next day. And since you were working late, others may come in before you the next day and make use of the WRONG information.

I would be surprised if corruption would occur, theorizing that the server doing the abrupt cut-off does at least some work to ensure that cached data is properly handled. But, again, if the data wasn't completely transferred, then I could see lost data.

The best I can offer as some documentary help is:
Server-wise:
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/fileio/base/file_caching.asp

Local-wise:
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/fileio/base/description_of_a_network_i_o_operation.asp

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/fileio/base/local_caching.asp

cheers