Install PUP into the PS3 from XMB (Settings > System Update > Update via Storage Media) Then put the renamed PUP into the folder you just create inside your USB‚ example: Rename the PUP inside the OFW 3.55 SONY folder (OFW3.55.PUP) to PS3UPDAT.PUP If you're on 3.55 CFW reinstall OFW from recovery mode then jump to step #3 If you're on 3.55 Official Firmware jump to step #3. Which firmware is currently installed on your PS3?
Create on the root of a USB (formatted FAT 32) the following folders: \PS3\UPDATE\