I use my phone to connect to Exchange 2010. I quit from Android due to battery life and went back to a old WM 6.1 phone.
In the first few days, I'm happy with Outlook Mobile for it's high efficiency and flawless integrated with Exchange 2010. This phone has upgraded Outlook Mobile in 2011 so I'm also happy with the threaded email function.
However, the phone sometimes reboot on it's own. Consider many apps have been installed on it, I don't think it's WM's problem but I gave it a 'hard reset'.
The good thing is, the system works quick w/o reboot. Unfortunately, it went back to a old Outlook Mobile w/o thread and in small fonts.
Google tells me the update is
https://update.outlook.com/cabs/OutlookLiveSetup.cab
The link above is already dead, but I ever saved the updater installation cab in my sd card and I believe it's same one, based on file name and file size.
But after I installed the updater, it ends with no connection to upgrade server. I believe MS removed the update files as well as the setup file above.
I tried some thread email from XDA, but all of them are for WM 6.5, so didn't work on my phone.
Upgrading my phone to 6.5 is no way.
Now I feel I'm abandon, and I guess that's how WM 7.0 user feel. If I can't get thread email back, I swear I will never buy a phone with 'Windows' logo.