I saw this post here,
Missing Folders and Tasks, and tried it's suggestion of getting the atl file from a backup. We went back a week and none of the backed up files restored the missing Folder and Tasks. I did not try renaming the atl file, because we have a lot of tasks and I don't want to have to recreate all of those triggers (I'm not even certain I could, even if I wanted to).
Oddly though, the jobs that were represented in the missing folder appear to still be getting triggered. It's as if there's a disconnect between what the system is doing and what it is showing in the Tasks List.
I'm hoping that someone might have a suggestion on how to get those things in synch?