Need to reboot Exchange before receiving incoming mail

[IS300]

We've been having problems with our exchange server lately. During the day, it runs fine, can send and receive internal and external messages.

Sometimes, overnight, it locks up or something. When I come in the morning, I don't have any external email in my inbox. I know this because I subscribe to a few mailing lists that normally send me messages early in the morning.

All I do is reboot the server, and also our ISA server just to be sure, then the messages come back in.

Does anybody have any suggestions as to what might be causing this? The only other thing on there is our Symantec antivirus.

Thanks in advance.

 

[fr33l3r]

Do you use restriction hours in exchange of ISA?

If you use OWA you can send yourself messages at night and review it directly with OWA to locate the problem.