by Heather P.
Thank you.
Managed to check those settings in my databases (MySQL) they all seem fine so it isn't that.
I'm on WIndows 2008 R2 servers and I have plenty of avaiable space for the backups to go to.
There are no .log files in the suggested location, in fact ther is nothing in moodledata/temp/backup folder.
Nothing I can see will exceed 4 gig.
There is nothing in any logs that I can find, it just looks like the process isn't starting rather than it is failing after it has started.
All very strange.
Thank you.