Question : SMTP Protocol Errors, Full Queues, Can't Send Emails

I keep getting these SMTP Protocol Errors on my Microsoft Exchange 2003 server::

Event Type:      Error
Event Source:      MSExchangeTransport
Event Category:      SMTP Protocol
Event ID:      7004
Date:            6/28/2010
Time:            1:55:33 PM
User:            N/A
Computer:      SBSERVER-1
Description:
This is an SMTP protocol error log for virtual server ID 1, connection #968. The remote host "74.125.45.27", responded to the SMTP command "rcpt" with "550-5.1.1 The email account that you tried to reach does not exist. Please try  550-5.1.1 double-checking the recipient's email address for typos or  550-5.1.1 unnecessary spaces. Learn more at                               550 5.1.1 http://mail.google.com/support/bin/answer.py?answer=6596 m11si2099611vcg.84  ". The full command sent was "RCPT TO:<[email protected]>  ".  This will probably cause the connection to fail.

For more information, click http://www.microsoft.com/contentredirect.asp.



I have a closed relay.
I've had the users change their passwords.
The server is up to date on Microsoft updates.
I use Postini Spam Filtering.  All looks fine there, in the sense that I haven't changed anything since I set it up originally.

I'm at a loss now.

These emails are filling my Queues.
The users can send email but they can't receive.

Any assistance would be greatly appreciated.

Answer : SMTP Protocol Errors, Full Queues, Can't Send Emails

In the properties of the Default SMTP Virtual Servers (in ESM, Server, Protocols, SMTP folder), Access Tab, Relay button: Disable the ability for authenticated users to relay "regardless of the list above".

Delete everything in the "C:\Program Files\Exchsrvr\Mailroot\vsi 1\Queue" folder (assuming it's overrun with spam).

My suggestion is to shut down SMTP inbound from the internet temporarily while you run the command below.  Also alert users that they may need to contact remote users to have them resend inbound messages and that they may need to resend any messages they sent recently.

Download aqadmcli.exe from ftp://ftp.microsoft.com/pss/Tools/Exchange%20Support%20Tools/Aqadmcli/aqadmcli.exe

Run aqadmcli.exe from the command prompt on the server
> setserver <ExchangeSERVERNAME>
> delmsg flags=all
Repeat until the Queue is clear.  Could take a while.
- The Exchange outbound queue is populated by the database so once you clear it, the database will repopulate it until all messages are either delivered (via SMTP) or deleted (via aqadmcli).

Re-enable SMTP from outside.