On my mac I activated FileVault1 about 4-5years ago. Unluckily i forgot the password as i never used it =(

I know root + user password to log in and do all the stuff (also as root in the console). As I would like to work with TimeMachine, now I need to rid of this old problem.

• Called mac support, they said I should go to the local mac support. This would be my last choice because of the price and the paid hours it will take for unlocking/copying. Maybe they have some keypairs for backdoors, otherwise I should be able to do the same.
• Found this filevault debuglog bug (2012), but its already 5yrs ago that I typed the password,so I dont think those log files still exist. Also because now I have the up2date version of ios.
• Found a tutorial which told me to delete /Library/Keychains/FileVaultMaster.keychain but to first switch it off, which I can't without the passwort.
• Tried to switch off FileVault with different username combinations of root/user. But he really really want the "main password".

Like now it is really useless: The system does not protect against "my person" (who lost the passwort) and at the same time it lets me work and do everything….

How do I switch filevault (version 1) off? OR

How do I reset the "masterpassword"? (or any other workaround is really appreciated)