I logged into my site today and all my categories and tags have vanished, however existing permalinks seem to still exist whilst already uploaded posts are in the right place still.
When I try to add a category or tag is just vanished straight after creation.
The only thing I have been playing around with is robots.txt - no site changes have been made!
Site url: http://totallybigbrother.co.uk/
Thank you in advance for any help!