Why can't WAN Outlook 2007/2010 users connect to Exchange 2007 server after Domain Admin password change?

So just to clarify. All the users at the main location are fine. They can still connect with Outlook no problem.

Its just the users at remote sites over an MPLS connection that can't connect to Outlook?

What is the error when they try and connect? Is it just server unavailable? What do you see from one of the remote users if you right click+hold SHIFT on the Outlook icon in the systry and select Connection Status or Test Autoconfiguration.

Changing the admin password should have no bearing.

Can these remote users connect to Outlook Web App?

So just to clarify. All the users at the main location are fine. They can still connect with Outlook no problem.  (Correct)

Its just the users at remote sites over an MPLS connection that can't connect to Outlook? (Correct)

What is the error when they try and connect? Is it just server unavailable? What do you see from one of the remote users if you right click+hold SHIFT on the Outlook icon in the systry and select Connection Status or Test Autoconfiguration. (It drops compatiblity mode Windows XP & attempts to reconfigure the client via autodiscovery)

Can these remote users connect to Outlook Web App? (YES)
Outlook-Error.docx

I assume the remote sites with the problem can ping the mail server by FQDN?

From the remote sites with the problem can they get to the URL you have specified for autodiscover in their web browser?

For example.... https://autodiscover.yourdomain.com/Autodiscover/autodiscover.xml

Yes.  We can ping by FQDN.

Have you tried Exchange Remote Connectivity Analyzer? If not try it to get more details of the connection error.

What about access to autodiscover via the web browser?

I opened a case with M$ last night & worked until 2am (still no resolution). I have tried the ERCA which was inconclusive.  I did not try auto discover from the client's browser, as we experienced port connectivity issues telnetting to TCP 25, 135 & 587.  We ran several packet captures & sent data to the network team.  I have a scheduled callback @ 9am.  Please continue to offer suggestions until this matter is resolved.  Thanks!

Just a couple of  questions;

Have verified all the exchange DNS records in your AD? Have checked the event logs both in PDC and exchange for a clue? Did you try restarting IIS in your exchange?

This almost doesn't even sound like an Exchange problem. But possibly a coincidence with a problem on the network. Maybe an issue with the MPLS network at your main site. If you do a continuous ping between sites, are you getting any packet loss?

Now sum up the issue;

remotely administer all DCs & User workstations at remote site is fine.
connectivity issues telnetting to TCP 25, 135 & 587 still persists.

Is the exchange box behind any FWs/UTMs etc..? can you give bit more details of your network?

I have verified the DNS records.  I have restarted Exchange IIS, as well as uninstalled Rollup 14.

We have 0% packet loss while sending continuous pings from each MPLS Branch to the main site (IP, Nebios & FQDN)

We have an MPLS network which connects each branch  (no ACL with branch communication).  It routes our "core processor" packets to the Data Center (with an ACL), but routes internet packets to our firewall cluster at the main branch.

but routes internet packets to our firewall cluster at the main branch.

Just for a test purpose;

Do you have any mobile users, using active sync? can you check if they are able to send and receive emails?

What about your SSL?

All exchange traffic from the internet works properly.  SSL & Activesync work with no problems routing into the network.

So it seems to be a kind of   Exchange firewall issues.  Have you tested the  connectivity between Exchange and Active Directory  using  PortQueryUI tool?

Zacharia - No I have not.  Can you detail please?

I used the port query tool & queried 25, 80, 135, 443 587 from 3 sites (main, branch1, branch2) to the Exchange Server.  From the main branch, all ports replied "listening".  From the branch1 & branch2, the ports replied "filtered".  I also open 3 ports on another Server in the main branch: 80, 135, 3389.  I queried those 3 ports from the main branch, all ports replied "listening".  I queried the same 3 ports from branch1 & branch2, all ports replied "filtered".  The test I just performed eliminates the MPLS issue.  I am now 100% certain it is on the Exchange Server.  Any thoughts?

The hotfix installation required a reboot of the Servers, thus the manual route was deleted from the Exchange Server.  After thorough analysis & historic documentation, we re-added the route.