Thanks. I did search the forum before posting.
I have checked permissions, the rest of the solutions unfortunately are out of my expertise.
I went through my visitor stats and noticed multiple attempts to login in on website in 2 days and various strange visits on moodle. The course folder is missing from my moodledata so I can only suspect someone gained access and removed it?
To top it all up, I do not have a recent back up. I will see what I can do with the host's backups.
Lucky not tooooo much work to redo