Try deleting the other file again, and this as well:
C:\Users\<username>\AppData\Roaming\GPSoftware\Directory Opus\Layouts\System\default.oll
Fully exiting Opus (via File / Exit Directory Opus) before deleting either file. If Opus is still running (even if no windows are open), then deleting the files may have no effect.
You may also get better results with a newer version of Opus, since 10 is many years old.