Windows server 2003 running on very nice hardware uptime of over 200 days, running Exchange 2003 and McAfee Enterprise with all the proper config and exclusions. Yesterday, the "system" process starting to sporadically take up 100% of the CPU resources on the server. Only other software on the server are the HP tools and our Spam filter (Sunbelt Ninja). We've had no problems like this at all in the nearly 1 year since this server has been running. There are no other indications of a problem and no other software installed. This seems to happen sporadically without a pattern. When it happens, users get a frozen outlook, remote access to the server is stopped until CPU usage returns to normal. Anyone have any ideas what could be causing it and what steps I could take to fix it?