If you’re using Filezilla to connect to a shared hosting account that uses cPanel, and your internet connection gets dropped during a transfer, you’re going to get an error from Filezilla when you try to reconnect after getting your internet up again.
Here’s how to clear that error:
Login to your shared hosting account.
In cPanel, go to “FTP Session Manager”
You should see a long list of “IDLE” connections. Delete each of them, one by one, using the “X” button beside each entry.
Logout of cPanel when all the ftp sessions have been deleted.
…and that’s it! You should be able to connect normally to your account through ftp again.