There are instance where you just bought a USB thumb drive. You have tons of confidential data in it and suddenly boom...the usb decided to go on write protected mode..
Assuming you have try the Modifying registry to enable write and also have try the llftool.exe but still fail..then are looking at the right place.,.
I have a solution for you.
Fill a pail with water.. Submerge the usb thumb drive in it and let it stay there for at least 10 minutes.
Then take the Usb thumb drive and plug it into your computer...
It should be totally screw up by now..
Well why do you want to that? Well if you want to claim warranty you need to surrender your faulty usb thumbdrive which is in write protected mode but there are a lot of sensitive data in it..so this is the only option you have :)
Note: Remember to dry the usb thumb drive before sending for warranty purpose.