You can resolve this by closing Toad, navigating to your user files folder, deleting all files that start with a ~, and then restart Toad. Your user files location is a subfolder of Toad’s application data directory and you can find its path in Toad Options on the General page. It is going to be %APPDATA%\Quest Software\Toad for Oracle\10.6 by default.
If you could be so kind as to zip those files before deleting and send the zip to me offline at michaelstaszewskiquest.com I’d appreciate it.
Thanks,
Michael