I have installed Yosimite Back up and Yosimite File Keeper on my SBS 2003. Once I did this people were unable to print getting RPC server not available. Also they were unable to open any of their documents that I have on the server. I have unistalled both Yosimite Back Up and the file keeper. I still have the same issue. The users have permission to open the documents and permission to print. It is like they are being block to access the server.