SBS 2011: Event 217 invalid header fields with Failure hrResult (0x800ccc63)

In case the SBS 2011/2008 POP3 connector returns the error 217 on Event Viewer under Microsoft-Windows-Small Business Server/Operational

One or more (x) e-mail messages in the POP3 mailbox account 'emailaddress@domain.com' on the POP3 server 'mail.domain.com' have invalid header fields. Because of this, the messages cannot be delivered to the Exchange Server mailbox 'mailbox@domain.com' in Windows Small Business Server. The messages are still on the POP3 server. To resolve this issue, connect to the POP3 mailbox account, and then manually retrieve or delete the messages.

“and then manually retrieve or delete the messages”  LOL!!!!

If you have a look in the pop3connector.log [ C:\Program Files\Windows Small Business Server\Logs\pop3connector ] :

[t 0] 09/06/11, 17:46:10: (POP3) [RX] 505 27477
[t 0] 09/06/11, 17:46:10: (POP3) [RX] 506 4446
[t 0] 09/06/11, 17:46:10: (POP3) [RX] 507 32528
[t 0] 09/06/11, 17:46:10: (POP3) [RX] 508 358136
[t 0] 09/06/11, 17:46:10: (POP3) [RX] .
[t 0] 09/06/11, 17:46:10: Downloading message 1 of 500.
[t 0] 09/06/11, 17:46:10: (POP3) [TX] RETR 1
[t 0] 09/06/11, 17:46:10: (POP3) [RX] +OK 8723 octets follow.
[t 0] 09/06/11, 17:46:10: Sending message 1 to the SMTP recipient allusers@XXX.COM...
[t 0] 09/06/11, 17:46:10: (SMTP) [TX] MAIL FROM: <SUBJECT EMAIL> RET=FULL
[t 0] 09/06/11, 17:46:10: Downloading message 2 of 500.
[t 0] 09/06/11, 17:46:10: (POP3) [TX] RETR 2
[t 0] 09/06/11, 17:46:10: (POP3) [RX] +OK 171731 octets follow.
[t 0] 09/06/11, 17:46:15: (SMTP) [RX] 501 5.1.7 Invalid address
[t 0] 09/06/11, 17:46:15: Failure hrResult (0x800ccc63) trying to deliver message id 1:
[t 0] 09/06/11, 17:46:15: SMTPRESPONSE:    * * *   !Failed!   * * *
[t 0] 09/06/11, 17:46:15:                  * * *              * * *
[t 0] 09/06/11, 17:46:15:                  * * *  0x800ccc63  * * *
[t 0] 09/06/11, 17:46:15:       Command: [SMTP_MAIL]
[t 0] 09/06/11, 17:46:15:     Completed: Yes.
[t 0] 09/06/11, 17:46:15:     IxpResult:
[t 0] 09/06/11, 17:46:15:   ---> ---> --->  hrResult: 0x800ccc63
[t 0] 09/06/11, 17:46:15:                pszResponse: 501 5.1.7 Invalid address
[t 0] 09/06/11, 17:46:15:              uiServerError: 501
[t 0] 09/06/11, 17:46:15:              dwSocketError: 0
[t 0] 09/06/11, 17:46:15:                pwszProblem: <none>

As you can see, the connector not validates the header, passing the ball with “Return-Path” error direcly to Exchange transport. The latter has the parameter MaxProtocolErrors setted to 5 ( LOL )

First of all you can try to set the “Default Domain” on the “Sharepoint Fax Receiver Connector”. To do this we can use this EMS command:

Set-ReceiveConnector -Identity ($Env:computername + "\Windows SBS Fax Sharepoint Receive " + $Env:computername) -DefaultDomain $Env:UserDNSDomain

If you are unlucky, try to increase the paramenter “MaxProtocolErrors”

Set-ReceiveConnector -Identity ($Env:computername + "\Windows SBS Fax Sharepoint Receive " + $Env:computername) -MaxProtocolErrors 500

Remember to restart POP3Connector and MSExchangeTransport