Enable/Disable add-ins

You can enable/disable add-ins in the following way;

Outlook 2007

1. Tools-> Trust Center…-> Add-ins.
2. At the “Manage” dropdown list at the bottom select which type of add-ins you would like to enable/disable.
3. Press “Go…” and make the changes.
4. For some add-ins you'll need to restart Outlook for changes to take effect.

Outlook 2010, 2013, 2016, 2019 and Microsoft 365

1. File-> Options-> section Add-ins.
2. At the “Manage” dropdown list at the bottom select which type of add-ins you would like to enable/disable.
3. Press “Go…” and make the changes.
4. For some add-ins you'll need to restart Outlook for changes to take effect.

Note 1: See this post if you get the error “The connected state of Office Add-Ins registered in HKEY_LOCAL_MACHINE cannot be changed.”.

Note 2: You certainly do not need to have all add-ins enabled for Outlook to work properly. Disabling unneeded add-ins can actually speed up Outlook as well. For an overview see: Which Outlook add-ins do I really need?

Managing add-ins in Outlook.