We're in the process of migrating from Exchange 2003 to 2010 (both servers are connected via an IPSec VPN), but cannot move all the users at once, so we will need a co-existence period.
Now, the problem is that a user on the 2010 server cannot see details on a 2003 user's shared calendar - i.e. it just shows "Busy". The other way around works perfectly fine - a 2003 user can see details on a 2010 user's calendar.
I've checked and re-checked, and it looks like the public folders have been replicated over from 2003 to 2010.
I've tried re-adding the mailbox permissions via the shell on Exchange 2010, but no luck.
I've tried "Outlook /cleanfreebusy", but that didn't help, and OWA is also not showing details.
Also, we were initially testing 2010 SP3, but were getting a lot of problems having it connect to the 2003 server (ex: running get-mailboxfolderpermission on a 2003 user from 2010SP3 would fail out with an ID 6 in Event Manager (Cannot open mailbox [path to 2003 server]/cn=Microsoft System Attendant [...]).
When we tested 2010 SP2, we did not get this issue.
Does anyone have any information that can shed some light on this for us?
Much thanks,
Jimmy.