Outlook Troubleshooting First Aid – disabling add-ins

A lot of Outlook issues are caused by various add-ins. So, disabling all add-ins is a useful step and should be the first step for Outlook troubleshooting.

Please note every add-in will be a subkey under the following subkeys.

HKEY_LOCAL_MACHINESOFTWAREMicrosoftOfficeOutlookAddins

HKEY_CURRENT_USERSoftwareMicrosoftOfficeOutlookAddins

HKEY_LOCAL_MACHINESoftwareMicrosoftExchangeClientExtensions

HKEY_CURRENT_USERSoftwareMicrosoftExchangeClientExtensions

So, to disable all add-ins thoroughly, we can follow the steps below.

1. Click start -> Run… -> Type "regedit" (without quotation mark) and Click OK

2. Locate the following subkey

HKEY_LOCAL_MACHINESOFTWAREMicrosoftOfficeOutlookAddins

3. Backup and Delete all subkeys under above subkey

4. Repeat step 1-3 for the remain 3 subkeys

HKEY_CURRENT_USERSoftwareMicrosoftOfficeOutlookAddins

HKEY_LOCAL_MACHINESoftwareMicrosoftExchangeClientExtensions

HKEY_CURRENT_USERSoftwareMicrosoftExchangeClientExtensions

Now, all add-ins are disabled. If the issue disappears, it means the root cause is a conflict between Outlook and some add-in. We can restore the registry back and delete them one by one to find out which one cause the issue.