If your exchange 2010 server is stuck on Applying Computer Settings during boot up it could be any number of things! First off make sure that noone recently disabled IPv6, that can screw up alot of things. if that has recently happened boot into safemode with networking, and re-enable IPv6. Another cause could be if someone has brought up another exchange server on your domain. You really hafto get the configuration perfect on the new exchange server before rebooting the original. otherwise the original willnot boot properly. if this may be the cause just shut down the new server and reboot the original. once it safely boots up you can bring the new one back up aswell.
Another possible issue is that your server was never placed in the proper groups. Check to make sure your exchange server is a member of the following:
Domain Computers, Exchange Domain Servers, Exchange Enterprise Servers, Exchange Servers
It may be different if your on a forest, but this is what solved the problem for me! If you have anything to add or need any help please comment!
