The connection just dies and has to be repaired or PC rebooted.The firewall is switched off(windows) and the wireless connection is shown as been not firewalled.
The router is a Belkin FSD 7633UK4A and the wireless adapter is Belkin FSD 7050UK.
The wireless connected PC with the problem is brand new and running XP.
Belkin advice lines are useless, they told me to reduce the routers MTU to 1400 fat lot of good that did. Plus you spend on average one hour trying to get to a voice you can barely understand!!
Also I cant enable file sharing but that's for another day......
Any ideas guys.............