Let’s say you are trying to delete a content type for some reason or another, and you get a message that you can’t delete it because the content type is in use.
Let’s also say that you went the extra step and deleted all lists using that content type and you STILL get the message…..What’s up with this?
There are a bunch of places, as it turns out, that it can still be hiding that need to be deleted also. I only found this out from a post on the internet after days of trying all kinds of things.
It turns out that even deleting all items from the recycle bin is not enough. If you go to Site Settings/Site Collection Administration/Recycle Bin in your Site Collection, you will see 2 items:
Once you delete all that, you should be able to successfully delete your content type.
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