I tried looking up the issue, and the only thing I found is to make sure the name and slug are unique (which they are) and they are not default categories, they are ones that were made by us.
]]>A little more information would be nice when things like this popup.
Specifically, I am trying to change the slug of a category to correct a typo (lkand instead of land) but each time I get this message.
Having dumped the database to a sql file I was able to locate a tag with the same slug and correct it, however a more verbose error message would have been a little more helpful.
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