SP1

SP1 install fails with: Couldn’t resolve the user or group “mydomain.local/Microsoft Exchange Security Groups/Discovery Management.”

Exchange SP1 fails during the install of the mailbox role, with the following error:

 "Couldn't resolve the user or group "mydomain.local/Microsoft Exchange Security Groups/Discovery Management." If the user or group is a foreign forest principal, you must have either a two-way trust or an outgoing trust.".

Couldn't resolve the user or group "mydomain.local/Microsoft Exchange Security Groups/Discovery Management." If the user or group is a foreign forest principal, you must have either a two-way trust or an outgoing trust.

The setup where I experienced this issue, is a new Exchange 2010 install, installed into an existing Exchange 2007 environment. But I have seen that others have similar issues, when upgrading to SP1.

There does not seem to be any official KBs on the issue. Just a lot of people experiencing the same issue. (reference from google). But I found a valid solution to the issue.

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