Normally this would be the case if you got stuck in the middle of an Export/Import/Clone (check again if you used the name I provided above and only looked alphabetically--I typed it wrong from memory), but there is another way: when you have the Export/Import/Clone utility (app) open, take a look at the URL. It will be something like:
http://<yourHubIp>installedapp/configure/123/main
The 123 here is the app ID, which you can get from your particular URL. Re-format that URL like this instead:
http://<yourHubIP>/installedapp/status/123
(i.e., replace configure with status and take out everything after the app ID)
Then, proceed with the last step from above: hit the Remove Export/Import/Clone button (in the bottom right) and try again.
