SYMPTOMS/PROBLEM:

(Recently, users are unable to open other authorized maiboxes in OWA, even, the administrator.)

After installing e2k10 SP2 RU4, users are unable to open additional mailboxes through OWA, if the primary SMTP email address of the additional mailbox is not in the accepted domain list.

Following exception is thrown in the owa window

Request
Url: https://dotnetserver.turcich.com:443/owa/
User host address: 192.168.0.1
OWA version: 14.2.318.2

Exception
Exception type: System.ArgumentNullException
Exception message: Value cannot be null. Parameter name: organizationId

CAUSE
This is due to a design change in Exchange 2010 SP2 RU4.

MS SUPPORT RESOLUTION
Add the SMTP Primary Email Domain to the ”Accepted Domain List”

WORKAROUND
Rollback to RU3

Link:
http://support.microsoft.com/kb/2777852/EN-US?wa=wsignin1.0