If you can't remember which email address you used then you will have to phone Technical Support. It's free of charge and linked under Useful Links at the top of this page.
The web page may take you through installing Virtual Technician which is fine, it first checks that your software is OK then you will be connected to the page that shows you the toll-free phone number.
Alright, Thank you so much!!
I just checked the UK site and it asks for the account email and your current email and I think one of those can be omitted if you don't remember it. Give it a try anyway.