I have an HP Proliant ML350 server which serves as a domain controller running Windows Server 2003 sp2. About once per week it stops communicating with my network; when this happens I cannot ping the server by IP address from any device, and I cannot ping any other device from the server despite the fact the connection status on the server shows it is connected at 100Mbps. I have installed the latest HP support pack which had no affect. I tried repairing the network connection at the time it stopped communicating and it cannot complete because it errors out while attempting to clear the ARP cache. Finally, I thought I found a solution when I read a forum thread talking about 'Routing and Remote Access' creating this type of problem. The routing and remote access service was enabled to allow dial-up access at one time but it is no longer needed so I disabled it about two months ago and the communication problem appeared to stop, until yesterday when the server lost communication again. I tried repairing the network connection, this time with the routing service disabled and the repair succeeded however the server still wasn't communicating. The only way I have been able to recover is to restart the server and then it is good for awhile until all communications stop again.