I have an odd problem with an Exchange 2010 installation (2 servers - both VMs). It was working fine until I had a power outage. After I got everything running again, I have no incoming email. At first, I tried to send myself an email using telnet but failed with an "insufficient system resources" error. I moved the incoming queue to another drive and I was able to send myself an email via telnet (the body didn't come through but the email itself did). I can also send email inside my org as well whether the sender and recipient are on the same server or not. Outgoing email also works. However, if I send an email from an outside souce (gmail) to my org, it fails. There is no NDR and I can find no messages stuck in a queue on the Exchange side but nothing show up at the client end regardless of which Exchange server the client uses. I don't know if this is related or not but I have another problem with my installation. On a couple of clients (both Windows 7 but 1 with Outlook 2007 and the other with Outlook 2010) the client is continually prompted for credentials. No matter how many times the credentials are provided, Outlook continues to prompt for them. I tried using OWA to see if this is an Outlook problem rather than an Exchange problem and it worked fine. The test email I sent myself weren't there so it also looks like it isn't an authentication problem between the Outlook client and the Exchange box. What else do I need to check? Thanks Bert

Hi, First, please verify if you have "allow annoymous connection" on your default receive connector on hub/edge server. Please try to telent domian.com 25 outside your network and then post here. Please try to mslookup your domian.com to see if you have correct mx record point to your hub/edge server. Please try to run ExBPA to have a health scan and then post the error information here. Xiu Zhang TechNet Community Support

You can do the SMTP test at https://www.testexchangeconnectivity.com/ Jonas Andersson | Microsoft Community Contributor Award 2011 | MCITP: EMA 2007/2010 | Blog: http://www.testlabs.se/blog | Follow me on twitter: jonand82

Well, I found the problem and it turned out to have nothing to do with Exchange. My firewall box had both TMG and UAG installed on it. UAG decided to go on a vacation causing it to block all incoming DNS Server requests and SMTP connections. But, because it was UAG causing the problem and not TMG, TMG monitoring showed absoloutely no attempt from the external network for either DNS or SMTP. I uninstalled UAG and everything is back to normal. Thanks for your replies. Bert

You shoulnt have TMG and UAG on the same box, they do different things and this isn't supported. I'd advise you to seperate the roles.Sukh

It's been a while since I have done anything with UAG but IIRC, UAG requires TMG in order to operate. If TMG is not on the box you install UAG on, it will install TMG before continuing with the UAG instalation. I'll have to look that up but that is the way I remember it. Bert

TMG installed part of UAG is OK, but installing seperatly isnt, if youhave done this then it's OK.Sukh

Oh, I didn't know that. In my case, TMG was already installed and everything did seem to work fine for a while. Then, UAG went sideways on me. Bert