Outlook Logging

While deploying an Exchange hybrid solution for a client the other day, I experienced some problem with free/busy information between the on-premises Exchange and Exchange Online. As such, I decided to turn on logging in Outlook to try to find out what was happening.

Enabling Outlook Logging

For Outlook 2013 and Outlook 2010

  1. In Outlook, go to the File tab > Options > Advanced;
  2. Under Other, select or clear the Enable troubleshooting logging (requires restarting Outlook) check box;
  3. Exit and restart Outlook.

For Outlook 2007

  1. In Outlook, go to Tools > Options;
  2. On the Other tab, select Advanced Options;
  3. Select or clear the Enable logging (troubleshooting) check box;
  4. Exit and restart Outlook.

Note: turn off logging after you complete your troubleshooting. If you don’t turn off logging, the log files continue to increase in size.

What information does logging record?

The logging option logs information about the following features:

  • Calendar transactions that are generated by Outlook features, by user actions, by the object model, or by the MAPI Calendar Table, including:
    1. Inbox autoprocessing

    2. Free/busy publishing

    3. Reminders

    4. Calendar item actions (creation, modification, or deletion)

    5. Resource booking

      The main purpose of the calendar logging feature is to quickly identify situations where, for example, meetings are inexplicably deleted from a calendar folder.

  • Free/busy time changes
  • Offline Address Book
  • Transactions for the Messaging Application Programming Interface (MAPI), which is used with Microsoft Exchange, POP3, Internet Message Access Protocol (IMAP), Simple Mail Transfer Protocol (SMTP), and Lightweight Directory Access Protocol (LDAP). A unique log file is generated for each Send/Receive action that you perform on these accounts.
  • Communications with Exchange, POP3, SMTP, and IMAP servers.

Notice that I mention free/busy in the list above. However, this is partially true… To explain what I mean, let us have a look at the next section.

Viewing the log files

Most log files are in plain text. To protect your data, the calendar log file is a binary file that cannot be read without a conversion process. Contact Microsoft Support for more information about calendar log files.

The log files are stored in subfolders of the Temp folder. By default, this folder is located in: c:\Users\username\AppData\Local\Temp

Note that by default, the Local Settings and AppData folders are hidden.

The following table shows the location and content of the various plain text log files.

Type of log file

Subfolder

File name

O2013

O2010

O2007

Outlook Autodiscover

Temp

olkdisc.log

No

Yes

Yes

Exchange ActiveSync

Temp/EASLogFiles

datafilename.bin

datafilename.xml

Yes

No

No

Availability service

Temp/OlkAS

date-time-fb.log

No

No

Yes

Availability service, OOF, and meeting suggestion

Temp/OlkAS

date-time-AS.log

No

Yes

No

Protection rules

Temp/OlkAS

date-time-PB4S.log

No

Yes

No

Unified messaging

Temp/OlkAS

date-time-UM.log

No

Yes

No

Unified messaging configuration

Temp/OlkAS

date-time-UMCFG.log

No

Yes

No

Out-of-office

Temp/OlkAS

date-time-oof.log

No

No

Yes

Meeting suggestion

Temp/OlkAS

date-time-ms.log

No

No

Yes

Outlook calendar

Temp/OlCalLogs

OLKCalLog_date-time.etl

Yes

Yes

Yes

Transport

Temp/Outlook Logging

opmlog.log

Yes

Yes

Yes

SMTP

Temp/Outlook Logging

emailaddress-Outgoing-date-time.log

Yes

Yes

Yes

POP3

Temp/Outlook Logging

emailaddress-Incoming-date-time.log

Yes

Yes

Yes

IMAP

Temp/Outlook Logging

IMAP-emailaddress-Incoming-date-time.log

Yes

Yes

Yes

HTTP DAV

Temp/Outlook Logging

HTTP-emailaddress-date-time.log

No

Yes

Yes

Outlook Hotmail Connector

Temp/Outlook Logging

OLC-emailaddress-date-time.log

OLC-date-time.log

emailaddress.txt

No

Yes

Yes

Out-of-office

Temp/Outlook Logging

date-time-oof.log

No

Yes

No

Outlook profile

Temp/Outlook Logging

PROF_OUTLOOK_threadID_

action_year.month.day_hour.minute.second.txt

Yes

Yes

No

Outlook sharing engine

Temp/Outlook Logging

Sharing Enginedate .log

Yes

Yes

Yes

Outlook-Windows Desktop Search indexing

Temp/Outlook Logging

datafilename.log

Yes

Yes

Yes

Outlook advanced ETW

Temp/Outlook Logging

Outlook-date-time.etl

Yes

Yes

No

Mailtips

Temp/Outlook Logging

date-time-mailtips.log

No

Yes

No

Free busy

Temp/Outlook Logging

date-time-fb.log

No

Yes

No

Outlook Sharing Engine

Temp/Outlook Logging

Sharing Enginedatetime-mailtips.log

Yes

Yes

Yes

Outlook first run process

Temp/Outlook Logging

firstrun.log

Yes

Yes

Yes

To my despair, and for some strange reason, free/busy information is only logged in Outlook 2010! This is a great, great feature and so useful that I simply don’t understand why it is not present in Outlook 2013…

Long story short, I had to install Outlook 2010 in a test machine and use it to troubleshoot my issues. Looking at the logs, I was able to identify the problem…

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