You are right, Ijack!
There's no way we can distinguish that indeed, which is why I recommended contacting our tech support for assistance.
Unfortunately, if the OP has really forgot his/her password, the only way to unlock that external WD Passport would be to format it and lose the data.
The password protection on the drive is there to prevent people from accessing your drive, redbart! If you've forgotten your password there's no way WE can determine if the drive is yours or not, only our tech support might be able to do that.
So make sure you contact them with this.
SuperSoph_WD