Microsoft KB Archive/275291

= XADM: Event ID 1051 Received Regularly on Exchange 2000 Server =

Article ID: 275291

Article Last Modified on 2/27/2007

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APPLIES TO


 * Microsoft Exchange 2000 Server Standard Edition

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This article was previously published under Q275291



SYMPTOMS
You receive events similar to the following in the Application event log on an Exchange 2000 Server computer:

Event Type: Error

Event Source: POP3SVC

Event Category: General

Event ID: 1051

Description:

Unexpected error condition: call to function CEncryptCtx::CheckServerCert resulted in error code 0x800cc801.

-or-

Event Type: Error

Event Source: IMAP4SVC

Event Category: General

Event ID: 1051

Description:

Unexpected error condition: call to function CEncryptCtx::CheckServerCert resulted in error code 0x800cc801.

They may occur at regular intervals (like every 10 minutes), or appear to be more frequent and random.



CAUSE
This event is logged when a client tries to log on to an Exchange 2000 server using POP3 or IMAP over Secure Sockets Layer (SSL) and the server is not configured for SSL.



RESOLUTION
For additional information about how to configure the Exchange 2000 server to allow SSL connections, click the article number below to view the article in the Microsoft Knowledge Base:

175439 XFOR: Enabling SSL For Exchange Server

If the server is not supposed to be configured for SSL, you need to track down which clients are attempting to connect using SSL. You can determine which client is causing the error messages to be logged in two ways:  Use a network traffic analyzer, such as Network Monitor, to capture traffic to the server. You should see connections being attempted to the Exchange 2000 server on either port 993 or port 995. You can then get the IP address of the computers that are attempting the connections. Use the Netstat.exe utility. Because the information store opens the SSL ports even when it is not configured to use SSL, you can run netstat -an at a command prompt on the Exchange 2000 server. Then look in the &quot;Local Address&quot; column for one or more lines that look similar to the following

192.168.0.1:993

-or-

192.168.0.1:995

where 192.168.0.1 is the IP address of your Exchange 2000 server.

The corresponding IP address in the &quot;Foreign Address&quot; column is the IP address of a computer that has a connection to the Exchange 2000 server on port 993 or port 995 in the preceding example.

After you have the IP address of the remote computer, you can change the configuration of the e-mail client so that it does not attempt to connect to the Exchange 2000 server using SSL.



MORE INFORMATION
The normal POP3 and IMAP ports and the POP3 and IMAP over SSL ports are:

Additional query words: 13002

Keywords: kbprb KB275291

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