Client has a LAN comprising about 8 windows xp professional computers and a windows server machine. My software runs on all 8 and share files stored on the server. A problem has arisen with the network this week whereby some computers cannot access the server, some computers can, some computers can no longer access the internet via a broadband router attached to one of the machines, others can, some can access the internet but when are accessing the internet they lose the ability to access the server for currently open programs (including windows explorer) and these need to be terminated and relaunched to restore connectivity to the LAN. Some computers behave normally. He has had a network guy out who cannot make sense of it and just suggests increased RAM on the server while I know nothing about networks myself but would like to help as it's making my software look bad. I'd be grateful for any suggestions
EDIT NEW INFORMATION (question 17 hours old) :
All the computers were on static IPs already. Changing the 'troubled' computers to "Automatically obtain an IP address" today seems to solve the issues. I did this via a remote desktop program so I'm not sure but it appears that communication to the server might have slowed slightly. The server is running Windows server 2003. Does this info give you any clues as to what happened? BTW even when 2 computers were down I was able to go from one to the other via the remote desktop program.
There doesn't appear to have been any duplication of IP addresses. The subnet mask was the same for all computers (255.255.255.0). The default gateway and DNS server addresses are identical and the same on all computers (both the one that works perfectly in all respects and the others). The Wins Server was blank but once I set a computer to automatically obtain an IP it then got an address there
Network topology as I understand it (could be wrong) : network hub and all computers including server cabled directly to this. Internet access is via a broadband (DSL?) router that is connected to the telephone landline and to one computer. This computer is one of the ones that gave trouble. Thanks for the help