My hotmail account was messing around so I thought I’d remove it and put it back on.
Go to add account … other ….fill in the boxes and it says this account already exists.
That’s not really that helpful. I have googled it before mr smarty pants comes along with a side splitting link to google.
Thank you.

have you quit Msil since deleting the account?

Tried that. Even though I’ve deleted the account would it still be stored somewhere else?

Is there anything visible in Mail > Preferences > Accounts relating to your Hotmail account?

No. Ive tried a Spotlight search and all it comes up with is voice over utility whatever that is.

Does this help?:

http://solutionowl.com/mac-mail-account-already-exists-capitan/

It says that logging out will wipe all iCloud data on mac. Is that serious?

That fixed it. Award yourself the STW badge of honour!