It’s been awhile since I’ve done an Exchange Server 2003 to 2010 transition and as I’m in the process of reconfiguring OWA for this client, I realized there were quite a few things I’ve come across in the past and forgot some key items during the migration. Since I’m bound to forget these again if I don’t do another migration for a few months, I thought I’d write this blog post to serve as a reminder for myself and perhaps help others who may come across the same problem.
You’ve reconfigured your public DNS records to have legacy.domain.com directed to your legacy Exchange 2003 server and updated your webmail / owa / mail .domain.com record to direct traffic to your new Exchange 2010 CAS server. With everything seemingly configured, you navigate to the Outlook Web App page of your Exchange 2010 CAS server from the internet and log in with a legacy user’s mailbox only to get the following error:
Your request couldn't be completed because no server with the correct security settings was found to handle the request. If the problem continues, contact your helpdesk.
User host address: 188.8.131.52
OWA version: 184.108.40.206
The reason why you’re receiving this error is because you haven’t set Exchange 2010’s CAS server for it to know what is the URL for your Exchange 2010 Outlook Web App and what is the URL for your legacy Exchange 2003 Outlook Web Access.
Open up your Exchange Management Shell and execute the following with the appropriate fields:
Get-OwaVirtualDirectory -server internalCASserverName | Set-OwaVirtualDirectory -externalURL https://webmail.yourDomain.com/OWA -Exchange2003URL https://legacy.yourDomain.com/exchange
Executing the command above won’t give you any confirmation (as with most cmdlets) so it will look something like the following:
From here on, the redirect for legacy Exchange 2003 users should work as expected.