Vicki,
Bert is a personal friend of mine, we practice in the same town in Maine. He has helped me out of numerous jams, and I can virtually guarantee that he'll help you out of this one.
Call him please. Since he didn't give me permission yet to post his phone number (try Googling RiverviewPediatrics/Brewer/ME), you may call me and I'll give you his number. I am at 207-356-0461.
His point about not installing AC onto the server is a very imporant one. Never install AC onto the server. Just have an AC folder that is shared so that all computers can link to it. Only the database resides there, not the installation.
The installations take place on the individual computers (clients), not the server. In this manner, your data should never get overwritten.
Hope either Bert or I can help you.