Question : Users cannot send emails anymore.....only domain admins can !!

Hi all, well we have 2 exchange 2003 servers (back end/front end) and a mail filter appliance from ISS, everything was working fine till 3 days back, users cannot send any message, they can receive though.....whenever they try to send any message they get a bounced email saying the following:

The following recipient(s) cannot be reached:

      on 11/21/2007 9:14 AM
            You do not have permission to send to this recipient.  For assistance, contact your system administrator.
            MSEXCH:MSExchangeIS:/DC=xxx/DC=xxx/DC=xxxxx:ack end server name>

Tried to add any user who faces this issue to the domain admins group, guess what? he can send email without any problems and that bounced email doesn't exist!!!
Last thing happened before that issue occured, was deploying a WSUS server that updated the exchange server with latest updates ( few security updates and exchange updates ) were added....If it is a microsoft patch that caused that problem, which one is it??? if it is something else that has to do with permissions and security, what can it be???

Please assist as soon as possible since its a very sensitive issue.



 

Answer : Users cannot send emails anymore.....only domain admins can !!

Q. After installing that patch on exchange 2003 SP2, will have to be given EXPLICITLY the send as permission too!!

Ans. Correct.

Explaination:
This patch was released by MS in June 2006 as most of the customers raised the issue; when full mailbox permission is assigned; Administrators can access any mailbox & can send email as CEO or as any person in the organization (considered as security threats).

But after installing this patch - BlackBerry kind of services hampered as BlackBerry account has Send As permission assigned on mailboxes of BlackBerry Users.

You can use script mentioned in
http://support.microsoft.com/kb/912918

Or follow
http://msexchangeteam.com/archive/2006/04/28/426707.aspx (Check the comments posted by various users after reading the articles. Follow any suitable method mentioned in Comments)