If you enable the Content Organizer feature in SharePoint, a library with the name DropOffLibrary is automatically created for you. This is the place where you drop off your documents, after which the content organizer rules kick in and move your documents to the appropriate target location.
I was doing some testing with this feature in a test site in SharePoint Online and wanted to clean up afterwards. So what I did was disable the Content Organizer feature. Result: no more content organizer rules, but the DropOffLibrary was still there. So of course I went into the library settings, expecting to delete it from there. Surprise: the link to delete the library is missing for the DropOffLibrary.
As it turns out, there is a property called AllowDeletion which is set to False for this library, probably because it is so tightly linked to the Content Organizer feature. What you would hope for is that feature deactivation causes this property to be set to True, but that’s not the case.
I tried a few other options, like deleting it through SharePoint Designer but you can’t delete it from there either.
Several blogs mention that you need to set the property AllowDeletion to True using PowerShell:
$list.AllowDeletion = $true
But unfortunately, that only works in SharePoint (2010, 2013) On-Premises. The property is a member of the Microsoft.SharePoint.SPList class, but not available as a member of the Microsoft.SharePoint.Client.List class, so not part of the CSOM (yet) and therefore deletion of this list cannot be set to allowed.
In other words, once you activate the Content Organizer in SharePoint Online, there is no way to get rid of the DropOffLibrary. What you can do of course is hide it as much as possible, but that’s not really cleaning up. So if you are considering the Content Organizer for a SharePoint Online site, make sure you want this because there is no complete way back.