One of our sites has two Hub Transport servers (Exchange 2007 SP3) and one Active/Passive Mailbox cluster (Exchange 2007 SP3). I notice that there are several hundred mails queueing on the Hubs for that CMS. Usually, if we have this issue, it's to do with the Hubs themselves and the reboot of the affect HT fixes it, but since we have two Hubs queueing mail I don't think it's them. What's the best way to find out what is causing the queueing? I'd rather not fail over the CMS just yet.

Is there an error listed in the queue viewer? Have you tried turning up logging on some of the Transport categories to see if there are any clues in the event log?Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."

There's no error listed in Queue Viewer, not sure what you mean by turn up logging for some Transport categories?

Get-EventLogLevel Look at the categories. Try turning some of them up to "Expert" and see if you get anything useful. You didn't say whether you'd looked in the event log, maybe there's something already there without turning up the settings. Going back to your original question, network errors or misconfigurations are usually the culprit. I'd recheck whether you have misconfigured Windows Firewalls, hardware firewalls between the servers, faulty NICs, faulty switches, loose connections, things like that. Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."

On Sat, 9 Jul 2011 10:50:24 +0000, TomD1976 wrote: > > >One of our sites has two Hub Transport servers (Exchange 2007 SP3) and one Active/Passive Mailbox cluster (Exchange 2007 SP3). > > I notice that there are several hundred mails queueing on the Hubs for that CMS. Usually, if we have this issue, it's to do with the Hubs themselves and the reboot of the affect HT fixes it, but since we have two Hubs queueing mail I don't think it's them. What's the best way to find out what is causing the queueing? I'd rather not fail over the CMS just yet. If nobody's getting any e-mail, why not?! Have a look at PerfMon and see what's up with RPC requests on the CMS. --- Rich Matheisen MCSE+I, Exchange MVP --- Rich Matheisen MCSE+I, Exchange MVP

Hi, Do you have any update? ThanksSophia Xu