Summary

Compared to earlier versions of Microsoft Outlook, Outlook 2010 and later versions provide an easy method to enable advanced logging: through Event Tracing for Windows (ETW). When you enable ETW logging, an event trace log (.etl) file is generated. You typically use ETW logging on the Microsoft Exchange server where you have a mailbox. In this situation, you experience one or more of the following issues:

  • Slow startup times

  • Irregular delivery of email messages

  • Slow display of views

  • Slow access to shared mailboxes

Note You may experience these issues for a variety of problems that may not be captured by this advanced RPC logging. For example, slow startup times can be caused by interactions with add-ins, and slow folder access can be caused by large mailboxes or folders. Neither of these problem scenarios can be analyzed by the advanced logging that is discussed in this article. For known performance issues that are caused by add-ins, large mailboxes, or folders, use the Microsoft Support and Recovery Assistant (SaRA) tool. For More information about SaRA, see the following article in the Microsoft Knowledge Base:

Fix Outlook and Office 365 issues with Support and Recovery Assistant for Office 365 There may be other issues that advanced logging can capture. If you aren't sure, contact a support engineer to help you with your support case before you enable advanced logging. The "More Information" section lists the steps that you can follow to enable global logging and advanced tracing. Additionally, it explains how to collect the log files after you have reproduced the problem when ETW tracing is enabled. Important To help protect customer data, the advanced trace log files are binary files that can't be read without a conversion process. You can upload log files to a secure location that is provided by Microsoft Customer Support Services. A support engineer from Microsoft can download and convert the log file for analysis.

More Information

Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:

322756 How to back up and restore the registry in Windows Note It is optimal to enable logging when you can reproduce the problem in real time. If you leave logging enabled for several hours or days, the problem becomes very difficult to analyze because too much information is captured in the log file.

Enable global logging in Outlook

When you enable global logging through the Outlook interface, Outlook generates both transport and advanced trace logs. The mail transport logs are text-based logs, such as OPML, IMAP, POP3, and SMTP. The advanced trace log contains advanced logging events. Advanced logging events include the following:

  • RPC trace events

  • Sync events

  • Exchange Web Services (EWS) events that are related to AutoDiscover, Availability Services, MailTips and Out of office (OOF).

Note In Outlook 2010, global logging changed after the RTM version of the product. To troubleshoot a performance issue or other unexpected behavior, you must first make sure that you are using the latest build of Outlook. For more information about the latest applicable updates for Outlook, see the following article in the Microsoft Knowledge Base:

2625547 How to install the latest applicable updates for Microsoft Outlook (US English only) To enable global logging in Outlook, follow these steps:

  1. On the File tab, select Options.

  2. In the Outlook Options dialog box, click Advanced.

  3. Scroll down the list of settings, and then select the Enable troubleshooting logging (requires restarting Outlook) option.

  4. Click OK.

  5. Exit Outlook.

  6. Start Registry Editor.

  7. Create the following registry value at the specified location. Note Manually create any registry keys or values if they don't exist. Also, unless there are specific instructions, all registry keys are the same for 32-bit and 64-bit versions of Microsoft Office. If the value already exists, make note of it. Subkey: HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\xx.0\Outlook\Options\Shutdown DWORD: FastShutdownBehavior Value: 2 The xx.0 placeholder stands for 14.0 in Outlook 2010, 15.0 in Outlook 2013, and 16.0 in Outlook 2016, Outlook for Office 365 and Outlook 2019.

  8. Exit Registry Editor.

  9. Restart Outlook, and reproduce your issue.

  10. After you have reproduced the issue, exit Outlook.

  11. After you send files to the Microsoft Support engineer, restore the original settings by disabling the logging from step 3 and by setting FastShutdownBehavior to the default value of 0, unless you noted an existing value in step 7.Note The log files are created in multiple folders. These folders vary, depending on the version of Outlook that you're running.

    Outlook 2010

    Log files in the %temp% folder

    File name

    Outlook RPC log

    OLKRPCLOG_date-time.etl

    AutoDiscover log

    olkdisc.log

    Outlook/SharePoint synchronization logs

    .htm and .xml files

    Log files in the %temp%\OlkAS folder

    File name

    Availability Service, OOF, and Meeting Suggestion log files

    date-time -AS.log

    Protection Rules log files

    date-time -PB4S.log

    Unified messaging log files

    date-time -UM.log

    Unified Messaging configuration log files

    date-time .UMCFG.log

    Log files in the %temp%\OlkCalLogs folder

    File name

    Outlook calendar log files

    OlkCalLog_date_time.etl

    Log files in the folder

    %temp%\Outlook Logging

    File name

    Outlook advanced ETW log

    Outlook-########.etl

    MailTips log

    date-time-mailtips.log

    OOF log

    date-time-oof.log

    Transport log file

    opmlog.log

    Outlook profile logs

    Prof_OUTLOOK_PID_OutlookStart_date_time.txt Prof_OUTLOOK_PID_OutlookStart_date_time.txt

    SMTP log files

    emailaddress-Outgoing-date_time.log

    POP3 log files

    emailaddress-Incoming-date_time.log

    IMAP log files

    IMAP-emailaddress-Incoming-date_time.log

    HTTP DAV log files

    HTTP-emailaddress-date_time.log

    Outlook Hotmail Connector log files

    OLC-emailaddress-date_time.log OLC-date_time.log emailaddress.txt

    Outlook Sharing Engine log files

    SharingEngine date.log

    Outlook-Windows Desktop Search indexing log files

    data file name.log

    Outlook first-run process log file

    firstrun.log

    Outlook 2013 and Outlook 2016

    Log files in the %temp% folder

    File name

    Outlook/SharePoint synchronization logs

    .htm and .xml files

    Log files in the %temp%\EASLogFiles

    File name

    EAS logs for Hotmail accounts

    .bin and .xml folders

    Log files in the %temp%\OlkCalLogs folder

    File name

    Outlook calendar log files

    OlkCalLog_date_time .etl

    Log files in the folder

    %temp%\Outlook Logging

    File name

    Advanced ETW log

    Outlook-########.etl

    Transport log file

    opmlog.log

    Outlook profile logs

    Prof_OUTLOOK_PID_xxxxxxxx_date_time.txt Prof_OUTLOOK_PID_LoggingStart_date_time.txt

    SMTP log files 

    Note The log files are only logged in Outlook 2016 and earlier versions.

    emailaddress-Outgoing-date_time.log

    POP3 log files

    Note The log files are only logged in Outlook 2016 and earlier versions.

    emailaddress-Incoming-date_time.log

    IMAP log files

    Note The log files are only logged in Outlook 2016 and earlier versions.

    IMAP-emailaddress-Incoming-date_time.log

    Outlook Sharing Engine log files

    SharingEngine date.log

    Outlook-Windows Desktop Search indexing log files

    data file name.log

    Outlook first-run process log file

    firstrun.log

    Note You can sort by Date modified to find the files that were created most recently.

Note The above steps 1 through 5 sets the following registry data:

Subkey: HKEY_CURRENT_USER\Software\Microsoft\Office\xx.0\Outlook\Options\Mail

DWORD: EnableLogging

Value: 1 The xx.0 placeholder stands for 14.0 in Outlook 2010, 15.0 in Outlook 2013, and 16.0 in Outlook 2016, Outlook for Office 365 and Outlook 2019.

Enable only advanced logging in Outlook 2013 and Outlook 2016

In Outlook 2013 and Outlook 2016, you can enable the advanced ETW logging without enabling global logging. If you use the following registry setting, the mail transport logs (POP3, SMTP, and so on) aren't generated. Additionally, the Outlook window title bar doesn't display the "Logging Enabled" string. To enable only advanced logging in Outlook 2013 and Outlook 2016, follow these steps:

  1. Exit Outlook.

  2. Start Registry Editor.

  3. Create the following registry values at the specified locations. Note Manually create any registry keys or values if they don't exist. Also, unless there are specific instructions, all registry keys are the same for 32-bit and 64-bit versions of Office. Subkey: HKEY_CURRENT_USER\Software\Microsoft\Office\xx.0\Outlook\Options\Mail DWORD: EnableETWLogging Value: 1 Subkey: HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\xx.0\Outlook\Options\Shutdown DWORD: FastShutdownBehavior Value: 2 Notes

    • If FastShutdownBehavior already exists, make note of the value.

    • The xx.0 placeholder stands for 15.0 in Outlook 2013 and 16.0 in Outlook 2016, Outlook for Office 365 and Outlook 2019.

  4. Exit Registry Editor.

  5. Start Outlook, and reproduce your issue.

  6. After you have reproduced the issue, exit Outlook.

  7. After you send files to the Microsoft Support engineer, restore the original settings as follows:

    • Change the value for EnableETWLogging to 0.

    • Change the value for FastShutdownBehavior to 0,unless you noted an existing value for FastShutdownBehavior in step 3.

Enable only Sync Issues Conflict logging in Outlook 2013 and Outlook 2016

To do this, follow these steps:

  1. Start Registry Editor.

  2. Create the following registry value at the specified locations.

    Subkey: HKEY_CURRENT_USER\ Software\Microsoft\Office\xx.0\Outlook\Options  DWORD: EnableConflictLogging Value:  0 = Never save Modification Resolution logs              1 = Always save Modification Resolution logs              2 = Save Modification Resolution logs when a "critical conflict" occurs Note The xx.0 placeholder stands for 15.0 in Outlook 2013 and 16.0 in Outlook 2016, Outlook for Office 365 and Outlook 2019.

  3. Exit Registry Editor.

To view the Modification Resolution logs, follow these steps:

  1. On the Navigation Bar, click  Navigation options .Navigation Bar

  2. Click Folders, and then locate the Sync Issues folder.  Note The Sync Issues folder is usually hidden unless you expand the folder list.

Performance Log Users group

If .etl files aren't generated as expected, add your user account to the Performance Log Users group on the workstation. To do this, follow these steps:

  1. Click Start, click in the Start Search box, type compmgmt.msc, and then press ENTER.

  2. Expand System Tools.

  3. Expand Local Users and Groups, and then click Groups.

  4. In the list of groups, right-click Performance Log Users, and then click Add to Group.

  5. On the General tab, click Add.

  6. Type your user name, or click Advanced to search the directory for your user account.

  7. When you have finished, click OK.

  8. Click OK again to close the Performance Log Users Properties dialog box.

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