"insufficient" memory when opening .rif

sorry to bug with a dumb issue, i have a .rif thats been working just fine until about an hour ago; it's suddenly removed itself from the "recent files" tab in painter and claims i dont have enough space when i try to open it (which isnt true). the only thing i can think of that i've fiddled with before this issue is that i deleted a second file under the same name as this one (painting.rif) but with .bak at the end. thanks in advance