We have a single Exchange 2010 standard server (Win2k8 Standard R2). Last nite mail stopped going out. Everything is simply sitting in the queue. Some messages were tagged with 451 4.4.0 Primary target ip responded with 421 4.4.2 connection dropped due to timeOUT.
Looks like everything is just stuck. Can I restart one of the Exchange services to see if it is hung up? Windows updates were run last week but it seemed to be fine.