Board Thread:Support Requests - Getting Technical/@comment-24208349-20140928200523/@comment-452-20140928202508

I know of three options:
 * Manually
 * With a bot or other automated script.
 * Special:Export, edit xml file to remove categories, Special:Import

There is also a 4th, temporary options:
 * Create the category page, and add __HIDDENCAT__ to it - this will hide the category from the bottom of the page, until you have a chance to remove it.