Filemaker pro client disconnect from database
We have Filemaker pro 13 Advance Server running in Mac 10.9.1. We have one datebase hosted on that server. About 15 people are accessing (using filemaker pro 13) it from LAN (local network) only two people are accessing it from WAN (outside office). The database keeps closing after a while, even some time while we are adding records or typing to update a record database cols. After disconnecting we are loosing our last data entered. In the log file it is " Client xxxx IP xxx no longer responding, connection closed (51).
On the client machine we get the following message ( Communication with the host was interrupted and could not be re-established. All affected windows will be closed.).
Any help please?
Thanks in advance.