Something caused one of our domain controllers to stop responding to requests a few moments ago. Upon investigation, the server appeared to be being bombarded by authentication requests. This caused the server to run out of memory, and stop responding all together. The server has been rebooted, and seems to be working properly. We are monitoring it closely, and investigating the cause of the problem.
Services that were affected and reported to the helpdesk include: Legacy webmail (Exchange 2003 Webmail)