Note If you re-enable an add-in that caused a performance problem at one time, you may experience performance problems in the future in the Office program under which the add-in is loaded. See the More Information section of this article for additional information on ways you can monitor add-in performance in Office programs.
In Office 2013 and later versions, the performance of add-ins is logged in the Application Event log under an Event ID: 45. The following figure shows an example event for an add-in load time in Outlook.
However, if an add-in causes performance issues in an Office program, an Event ID: 59 is added to the Application Event log. For example, the following event shows that an add-in was disabled because it caused Outlook to shut down slowly.
Event ID: 59
Task Category: None
Outlook disabled the following add-ins
Load Behavior: 3
Threshold Time (milliseconds): 500
Time Taken (milliseconds): 719
Disable Reason: This add-in caused Outlook to close slowly.
Policy Exception (Allow List): 0
In this scenario on the next launch of Outlook, the following notification will be shown to raise an alert that an add-in was disabled.
By clicking View Disabled Add-ins, the Disabled Add-ins dialog box is displayed and you can click the Always enable this add-in option to keep the add-in enabled even if it performs slowly.
If you click Always enable this add-in, the registry is updated to include details about the add-in that is to be exempted from this automatic disabling feature.
DWORD: <ProgID of the add-in>
Value: Hex value between 1 and A indicating the reason the add-in was originally disabled. (see table below)
0x00000002 Demand load (LoadBehavior = 9)
0x00000004 Handling FolderSwitch event
0x00000005 Handling BeforeFolderSwitch event
0x00000006 Item Open
0x00000007 Iteration Count
0x00000009 Crash, but not disabled because add-in is in the allow list
0x0000000A Crash, but not disabled because user selected no in disable dialog
NoteThe x.0 placeholder represents your version of Office (16.0 = Office 2016, 15.0 = Office 2013).
Disabling an add-in that was re-enabledIf you re-enable an add-in by clicking the 'Always enable this add-in' option, you should consider manually disabling the add-in if you continue to experience slow performance or instability issues in Outlook. Use the following steps to manually disable an add-in that was previously re-enabled using the 'Always enable this add-in' option:
- On the File tab, click Slow and Disabled COM Add-ins in Outlook 2016 or click Slow and Disabled Add-ins in Outlook 2013.
- Click 'Disable this add-in' below the add-in you want to disable.
- Click Close.
- Exit and restart Outlook.