I have a situation where a client has two sites.
Site1 houses the SBS2008 server and all clients here use the domain-a.com email address.
Site2 its own SBS2008 server but we're now configuring all of it's clients to access their mail through site1's server. These clients use domain-b.com for their email addresses. We've added an accepted domain in Exchange and configured an email policy that assigns the correct email address to these domian-b clients. This part works fine and mail is accessible via OWA, Blackberry and I've configured my own PC with mail profiles to connect to these domain-b mailboxes. I'm running Win7 and Outlook 2010 and it works just fine.
The problem I'm having is the domain-b client machines run Win7 and Outlook 2007 and this appears to keep changing the proxy server and MSSTD value when Outlook is closed. This is the process:
1. Configure exchange profile via control panel setting as follows:
Proxy server: https://office.domain-a.com
Connect only to: msstd:office.domain-a.com
Un-tick the 'on fast networks...' box
Tick the 'on slow networks...' box
Proxy authentication set to Basic (although I've also tried this set to NTLM).
2. Open Outlook - Everything works just fine.
3. Close Outlook
4. Check the mail settings and find that the proxy is now set to https:office.domain-b.com
Obviously, now the DNS won't resolve and the certificate won't match. If you change the values back again, you can open Outlook and it will work fine. However, closing outlook rewrites these incorrect values back to the Outlook settings.
I should be clear and say that the domain-a.com people are having no issues and my Outlook 2010 works fine on both domains and my settings don't get re-written.
I'm having to assume at this stage that there is a bug with Outlook 2007 which looks at the domain name of the email address and re-writes this into the proxy settings.
I'm running Microsoft updates on one of the domain-b machines at the moment but there doesn't seem to be anything Outlook or Office based in the list of available updates.