If your PS3 is on 3.66 then it will not work. Since you have a usb jailbreak, I am assuming that you most likely bought one. I am also assuming that it is only for 3.41 or 3.55.

What is your PS3's current firmware and what kind of jailbreak do you have?

Here is a link to one of the best CFW's out You must login or register to view this content. or you could even install Linux with an OtherOS++ pup here is a direct download link for that You must login or register to view this content. and you can also QA flag your console if you install the otherOS++ .pup with the QA flag.pkg heres a direct download link for that as well You must login or register to view this content.. to perform the jailbreak you conslole has to be on 3.55 or lower and all you have to do is put the CFW (i provided the link) onto a usb drive name the .pup file PS3UPDAT put that in a folder named UPDATE and then put that folder in another folder named PS3 plug it into your ps3 and go over to system update then update via storage media and then the CFW will begin installing

No use trying until you tell us your firmware version, look on your PS3 under System Information then report back.