I am currently working for an organization who is company A and we have just acquired a different company of like 1,000 folks. We both have separate forests with no trust and both using Exchange 2010. I was approached because the users have to check their email in basically two places which is a nightmare. What we are trying to do is come up with a temporary way to have the users to be able to check email in one place with two different forests who using exchange 2010. I have been reviewing this myself and thought of things anywhere from setting up a connector to forward email to setting up a internal relay. I figured I will ask the professionals now. What is the best solution to allow two separate companies who do not have a trust but Our autodiscover entry is on the internet to connect and check email in one place. They also VPN to our network to check email.
I am also wondering if this can be done in DNS. If I was going to do this in DNS how would I point all the mail to go to another domain if this is even possible.