Script to DISABLE Auto Complete in Outlook for all versions of Outlook
So after a staggered Domain Migration (Cross Forest) and having issues with users repeatedly relying on the Auto Complete for their address’ lookup in outlook, I decided to DISABLE AUTO COMPLETE in OUTLOOK company wide.
Relying on Auto Complete is normal user behavior, but due to a user being migrated to a new domain, this cached address would no longer connect to the user’s mailbox, thus sending a return to sender email.
To make life simple, we disabled Auto Complete in Outlook on both domains, with a simple way to reverse it once we had everyone migrated.
Instead of writing a custom GPO, this was deployed as a batch file, using Group Policy.
REG ADD "HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\12.0\Outlook\Preferences" /t REG_DWORD /v ShowAutoSug /d 0 /f REG ADD "HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\13.0\Outlook\Preferences" /t REG_DWORD /v ShowAutoSug /d 0 /f REG ADD "HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\14.0\Outlook\Preferences" /t REG_DWORD /v ShowAutoSug /d 0 /f REG ADD "HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\15.0\Outlook\Preferences" /t REG_DWORD /v ShowAutoSug /d 0 /f REG ADD "HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\16.0\Outlook\Preferences" /t REG_DWORD /v ShowAutoSug /d 0 /f Exit
Once you create this as a “.bat” file, deploy it using Group Policy as a Login Script of your domain.
Once added as a Login Script, Auto Complete will be disabled in Outlook.
To REVERSE and re-ENABLE Auto Complete in Outlook, simply change the value from 0 to 1.
After a reboot or gpupdate, the Auto Complete will again work for your users.