We are upgrading to Exchange 2010 from 2007. Our current configuration while we test is the 2007 server is still sitting in front and passing mail back to the 2010 server and people are logging in to the correct OWA server manually. I currently have mail flowing between servers and outbound with no problems but when it comes to mobile devices I am having issues. We have both BlackBerry and iPhone/Droid type devices. The BlackBerry I can probably get resolved since it uses the BES server but the iPhone/Droids I am having a problem with. So far I cannot even get them connected to the old or new external addresses. Should these phones automatically use the new server once their mailbox is moved or will I have to have them all change the mail server in their phones manually?

Make sure there is no external URL set on the activesync virtual directory. This is a known issue with 2010 and activesync devices receiveing 451 redirection errors. Go in emc on 2010 server, click on server configuration\CAS server\activesync and remove the external url. see http://blogs.technet.com/b/exchange/archive/2009/11/20/3408856.aspx

That didn't work.. I had actually updated it because I noticed it had my 2007 servers url so tried it with the 2010 and with it blank. Testing with an iPad that works when the account is on 2007 gives me a "cannot get mail the connection to the server failed" error on the 2010 server when I point it at the external 2010 address. When I try pointing it at the 2007 address I get a cannot verify account which I pretty much expected since his account is on the 2010 server now. Maybe this will work fine when we swap the 2010 into the primary front end position but we don't want to do that yet. I have no problems pointing them at the new external address for now but oddly that is not working either.

Ok, do you have multiple sites? If so, remove the inetrnal url as well from Exchange 2010 CAS servers.

No just 1 site. I actually got the iPhone to sync to the temporary new url for the 2010 server but I really dislike the way I had to make it work I found the "answer" here http://blog.nick.mackechnie.co.nz/post/2009/11/20/Exchange-2010-Active-Sync-Issue.aspx after noticing that my event log was saying Exchange ActiveSync doesn't have sufficient permissions to create the "CN=Steve, OU=Outside Sales,OU=90,OU=Branches,DC=xyz,DC=local" container under Active Directory user "Active Directory operation failed on DC3.xyz.local. The "fix" which I really hesitate to call it one was to go into my DC go to his account and enable inheritance on the security tab. This will suck horribly if I need to do this for every one of my users that has mobile devices. I have a lot of them. I managed to get a test iPad on that account to sync pointing at both server addresses by removing the external url from both servers so that part is golden just hoping there is a better way for the permission issue.

The article below has useful info for fixing permissions inheritance issue. http://www.exchangemaster.net/index.php?option=com_content&task=view&id=165&Itemid=57&lang=en

The article below has useful info for fixing permissions inheritance issue. http://www.exchangemaster.net/index.php?option=com_content&task=view&id=165&Itemid=57&lang=en Ok this helps a bit but still tells me I have to do what I did above which sucks. I am wondering why these accounts go marked as protected since they are not administrator accounts. Is there a way to find out why they are? A couple accounts are marked this way that never were any type of admin role and are not checked as protect from deletion.