You may come across some issue with outlook regarding add-in, if you notice something disappear in outlook, this might be a add-in that has disabled it self. Microsoft Outlook disables add-ins if the add-in error or takes a long time to load. To get around this you may need to force the add-in to be always on.
To enable add-ins that outlook has disabled.
Click File -> Slow and Disabled Add-ins as shown below
You will get a dialog like this
I noticed my gpgOL add-in disappeared so ill Always enable this add-in so outlook will ignore how slow it will make outlook.
Disable add-ins you don't need.
Disabling add-ins might be useful if your outlook it running slowly.
Click File -> Options -> Add-Ins you should get the dialog shown below.
Uncheck the add-in you want to disable. Again I’m using GpgOL for this example.
Click OK, restart Outlook and the add-in will be disabled