Resetting dat-files
I got the advise to reset some dat-files to solve my issue. Where can I find these and what do they do?
The most common dat-files that can be reset for troubleshooting are outcmd.dat and extend.dat. To reset them you can browse to their location and rename them to .old when Outlook is closed.
outcmd.dat
Keeps toolbar customizations. Resetting this will restore the Toolbar to default and recreates the icons that some addins might have installed.
extend.dat
Keeps a registry cache of addin settings. Resetting this will force Outlook to retrieve the settings from the registry again.
Windows XP
outcmd.dat: C:\Documents and Settings\%username%\Application Data\Microsoft\Outlook
extend.dat: C:\Documents and Settings\%username%\Local Settings\Application Data\Microsoft\Outlook
Windows Vista
outcmd.dat: C:\Users\%username%\AppData\Roaming\Microsoft\Outlook\
extend.dat: C:\Users\%username%\AppData\Local\Microsoft\Outlook\
To easily locate the folders for you, you can also use OutlookTools (free!)
Related Categories; Background info, Configuring, Errors
