Ubuntu One :: Repeated Sync Of Nonexistent File

U1 is trying to sync a file which doesn't exist on any of the devices attached to the account nor in the cloud folder. I've tried using U1sdtool to stop it, including the following commands:

I've also tried actually creating a file of the same name that it keeps trying to sync in the hopes that it will latch onto that one instead, but no go. I tried deleting that file, but no go. It constantly loops through the same nonexistent file, over and over and over and over and over...

It also only does this on one device. It does not do that on the other devices.

And, yes, I've done u1sdtool --waiting, and there is the nonexistent file, on the list, with all of the real files that actually do need to be synced backed up behind it.