Messed up thumbnail

After uploading post #904218 I noticed that the thumbnail is screwed up, for some reason it shows a broken thumbnail for post #904211 .

This the first time this has happened to one of my uploads. Can the thumbnail be fixed or will I need to reupload the image from scratch?

I put it in the missing thumbnail pool which should force it to re-generate a thumbnail next time the script runs.

Does the pool still work? I tried putting post #2910643 in it and nothing happened.

Isn’t that pool marked as deleted? Use the missing_thumbnail tag instead.