by Ken Task.
Was referring to purging Moodle caches ... but you are correct ... in a way for OS's - swap space is a 'cache' ... which on standalone servers - DB + code could be DB's.
The error on copying just some courses usually shows a module ID number I thought. Those are tricky to find and explore - have to go the course itself and inspect which module/type etc.
When copying courses, I leave it right there on the last screen rather than going onto other things ... I wanna see it finish!
Sorry ... no 'magic' answer here!
'SoS', Ken