Article ID: 255125
Article Last Modified on 8/6/2002
APPLIES TO
- Microsoft BackOffice Small Business Server 4.5
This article was previously published under Q255125
SYMPTOMS
The connector for Post Office Protocol 3 (POP3) mailboxes retrieves e-mail messages from POP3 mailboxes, but may not deliver them to the correct recipients. When this occurs, no error messages are reported in the event logs.
CAUSE
This behavior can occur if the Internet Mail service (IMS) for Microsoft Exchange is configured to require authentication and/or encryption for hosts that connect to the Simple Mail Transport Protocol (SMTP) interface.
RESOLUTION
To resolve this issue, use either of the following methods.
Method 1
Disable authentication and encryption on IMS:
- Start the Microsoft Exchange Server Administrator tool.
- Click Connections, and then double-click Internet Mail Service.
- On the Connections tab, click From any hosts (secure or non-secure) in the Accept Connections box, and then click OK.
- Stop and restart the Microsoft Exchange Internet Mail service by using the Services tool in Control Panel to apply the changes.
- Stopping the Internet Mail service also stops the POP3 connector. Manually restart the POP3 connector by using the Services tool in Control Panel.
Method 2
If you need to use authentication, use the Specify by host setting to specify the Small Business Server-based computer's IP address, and specify the Accept connection from this host setting:
- Start the Microsoft Exchange Server Administrator tool.
- Click Connections, and then double-click Internet Mail Service.
- On the Connections tab, click Specify by host.
- Click Add, and then type the IP address of your internal network.
- In the Subnet Mask box, type 255.255.255.255.
- Click Accept connection from this host, and then click OK.
- Stop and restart the Microsoft Exchange Internet Mail service by using the Services tool in Control Panel to apply the changes.
- Stopping the Internet Mail service also stops the POP3 connector. Manually restart the POP3 connector by using the Services tool in Control Panel.
MORE INFORMATION
The POP3 connector connects to the IMS SMTP interface to route incoming POP3 e-mail messages. If IMS is configured to require authentication and/or encryption, the POP3 connector cannot route e-mail messages successfully.
You can enable the Maximum Logging for SMTP Client Transactions option under the Delivery Service category on the POP3 Connector Diagnostic Logging tab. Event ID 4032 for the POP3 connector then displays the results of the SMTP transaction. Event ID 4022 displays the SMTP transaction transcript:
If the mail address of the sender is an invalid SMTP mail address, the SMTP transaction transcript will indicate an error 553 malformed address followed by the invalid SMTP mail address. Examples of invalid mail addresses include, but are not limited to: "username", "user@domain", and "First Name, Last Name".
A valid mail address appears as "user@domain.com".
NDR Status Code:502 Error Code:00000000 SMTP Reply:553 malformed address: <invalid mail address> SMTP Name:<user>@<sbsserver>.com SMTP Host:SBSSERVER NDR Status Code:600 Error Code:000006c0 SMTP Reply:553 malformed address: <invalid mail address> SMTP Name:<user>@<sbsserver>.com SMTP Host:SBSSERVER
An example of a successful SMTP transaction transcript is shown below:
NDR Status Code:1 Error Code:00000000 SMTP Reply: SMTP Name:<user>@<sbsserver>.com SMTP Host:SBSSERVER
Additional query words: smallbiz
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