editor vanished

Hi,

I added a new theme, a couple of plugins, and the editor on new posts has gone

I tried removing the new additions but it has not put back the editor

I did try and add one plugin before and it caused a memory error so I removed it again. That threw up a load of errors in the settings page

Once I changed the pages the errors vanished and the site is fine now but I have no way of adding posts at all

I have tried to re-install WP. No editor
I have re uploaded a new copy of WP over writing the old – no editor

I even tried to add a plugin that removes the visual editor lol and then remove that, to see if that kick started it

No editor

Anyone have a clue please?