ArcGIS Online and Portal for ArcGIS: This group is protected and cannot be deleted

Error Message

In ArcGIS Online or the ArcGIS Enterprise portal, attempts to delete a group fail with the following error:

Error:   
This group is protected and cannot be deleted.

Cause

The 'Deletion management' setting is enabled in the group setting. In some instances, the 'Deletion management' setting cannot be disabled when the group is linked to a distributed collaboration.

Solution or Workaround

Follow the instructions below to disable the group's Deletion management setting.

Note:
For distributed collaboration groups, delete the collaboration or the collaboration workspace linked to the group before performing the workflow below.

1. In ArcGIS Online or the ArcGIS Enterprise portal, click Groups. Browse to and click the name of the group to open the group's item page.
2. On the item page, click Settings.
3. Under Deletion management, disable the Prevent this group from being accidentally deleted option.