How to enable transport logging in Outlook

Microsoft Outlook supports the logging of the communications that occur between Outlook and various types of e-mail servers. These logs can be helpful when you troubleshoot problems with the transfer of messages between Outlook and the e-mail server.

Outlook can log the communications with Microsoft Exchange, Post Office Protocol version 3 (POP3), Simple Mail Transport Protocol (SMTP), Internet Messaging Access Protocol (IMAP), and Hotmail servers.

How to Enable Logging

Follow these steps to enable logging:

1. On the Tools menu, click Options.
2. Click the Other tab
3. Click the Advanced Options button
4. Click to select the Enable mail logging (troubleshooting) check box.
5. Click OK to save the setting, and then return to the main Options screen
6. Click OK.
7. Quit and restart Outlook.

From this point on, every time Outlook sends or receives messages, the communication that occurs between Outlook and the e-mail server is written to a log file.

NOTE: It is very important to disable logging after the logs have captured the failed communication with the server. If you do not disabled logging, the logs continue to grow indefinitely.

Log File Locations

The log files are in plain text format and are placed in the following locations:

• POP3, SMTP, MAPI
  
  The POP3, SMTP, MAPI transport types are written to a single log file in the following locations.
  
  On Microsoft Windows XP, and Microsoft Windows 2000:
  C:\Documents and Settings\<logon name>\Local Settings\temp\OPMLOG.LOG
  On Microsoft Windows 98, Microsoft Windows 98 Second Edition, and Microsoft Windows Millennium Edition (Me):
  C:\Windows\temp\OPMLOG.LOG
• IMAP Logs
  
  On Windows 2000:
  C:\Documents and Settings\<logon name>\Local Settings\temp\Outlook Logging\<NameOfIMAPServer>\IMAP0.LOG, IMAP1.LOG, etc
  On Windows 98, Windows 98 Second Edition and Windows Millennium Edition:
  C:\Windows\temp\Outlook Logging\<NameOfIMAPServer>\IMAP0.LOG, IMAP1.LOG, etc
• Hotmail Logs
  
  On Windows 2000:
  C:\Documents and Settings\<logon name>\Local Settings\temp\Outlook Logging\Hotmail\Hotmail0.LOG, Hotmail1.LOG, etc
  On Windows 98, Windows 98 Second Edition and Windows Millennium Edition:
  C:\Windows\temp\Outlook Logging\Hotmail\Hotmail0.LOG, Hotmail1.LOG, etc

NOTES:

• IMAP and Hotmail accounts generate one log for each Send/Receive action that you perform on these accounts (the log files are named Hotmail0.LOG, Hotmail1.LOG, etc.).
• If you have multiple Hotmail accounts configured, the folders where the logs are placed are named Hotmail, Hotmail 1, Hotmail 2, etc.
• You may have to close Outlook for the logs to be written to the log files.