Where Them
Logs AppWTLA-01

Microsoft Outlook

2 log locations · Windows, macOS

Microsoft Corporation · Vendor documentation

Where Microsoft Outlook keeps its logs

Microsoft Outlook logs to %TEMP%\Outlook Logging\ on Windows.

Microsoft Outlook logs to ~/Library/Containers/com.microsoft.Outlook/Data/Library/Logs/ on macOS.

Paths are printed exactly as Microsoft Outlook writes them. Environment variables like %LOCALAPPDATA% and $XDG_STATE_HOME are never expanded, so a path can be pasted straight into a shell. Where a path differs between installer types or shipping flavours, each one is racked as its own card below - why that happens.

Finding your way around Windows and macOS.

How to turn on debug logging for Microsoft Outlook

  1. Classic Outlook: open File > Options > Advanced.
  2. Classic Outlook: under Other, select Enable troubleshooting logging (requires restarting Outlook).
  3. Classic Outlook: restart Outlook. The title bar then shows (Logging Enabled).
  4. Classic Outlook: to set it in the registry instead, set DWORD EnableLogging to 1 under HKEY_CURRENT_USER\Software\Microsoft\Office\<1x.0>\Outlook\Options\Mail.
  5. Classic Outlook: for sign-in and activation problems, run reg add HKCU\Software\Microsoft\Office\16.0\Common\Logging /v EnableLogging /t REG_DWORD /d 1.
  6. macOS: choose Window > Sync Errors, click the gear icon, select Turn on logging for troubleshooting, then OK.
  7. macOS: restart Outlook and choose Leave Logging On.
  8. Switch logging off when you are done. The logs keep growing until you do.

How to collect Microsoft Outlook logs

  1. Classic Outlook: reproduce the problem, then close Outlook. It keeps diagnostic data in memory until it shuts down.
  2. Classic Outlook: open %TEMP% and copy the newest Outlook*.etl file. That is usually all that is needed.
  3. Classic Outlook: for mail transport problems, also copy opmlog.log and the Outlook Logging folder from %TEMP%.
  4. Classic Outlook: hold Ctrl, right-click the Outlook icon in the notification area and choose Connection Status or Test Email AutoConfiguration.
  5. macOS: open ~/Library/Containers/com.microsoft.Outlook/Data/Library/Logs/ and copy the Microsoft outlook-<date>-<time>.log files.