I'm currently in an environment with a Windows Server 2003 machine running AD and Exchange Server 2007. We have all our users, and a couple of general mailboxes (for example, "customer service") in AD and Exchange.
All my users have added these general mailboxes in their Outlook (Outlook 2007, Windows XP SP3), where they read mail and answer from the same box. This haven't been much of a problem until recently, where a couple of users just can't send mail from the mailboxes. It gives an error message saying they are trying to send mail on someone else's behalf and they don't have permission to do so.
All the mailboxes are set up the same way. All users have the "Send on behalf"-permission you can find when going to the Preferences of the particular mailbox, as well as the "Full Access Permission". The users reporting this problem have these same permissions as anybody else, yet Exchange won't let them send their mail.
I'm pretty new to Exchange, and this is driving me nuts. It's seems so easy with two permissions being set, and I just don't know where to look. Any guidance would be greatly appreciated.