(adsbygoogle = window.adsbygoogle || []).push({}); I'm trying to downgrade to 3.55 to change my MAC address, but I keep getting errors like "the system update is not compatible for the system" or "800" errors.

I'm currently on Rebug 4.78 DEX.

I've tried a number of downgraders, even the ones on the Rebug website.

Can someone please help me?

If you have QA Flags toggled you should be able to just install 3.55 without having to downgrade.

QA Flag is Enabled in Rebug Toolbox, But How Do I Install It?

put the PS3UPDAT.pup on your USB which should be formatted to FAT32 then put your USB into your PS3 and make sure you turn the internet off under Network settings then go to System Update and update from USB.

That's what I do but it gives me errors or where it shows the 3.55 UPDATE in System Update; It's grayed out & when I click it it gives me an error.

Have you tried installing it from the Recovery menu?

Yes, some has worked, but when it finishes installing, it prompts me to rebuild the database and as soon as it starts it says "could not rebuild database" and prompts me to format the database. And if I press circle it says "the hard disk could not be found"

Hmm that shouldn't be happening. Are you trying to install 3.55 CFW or OFW?

3.55 cfw

That makes it even stranger as that shouldn't be happening with 3.55 CFW. I'm starting to think that maybe to avoid all this BS you might be better off using the newest SEN Enabler to change your MAC. It resets everytime you restart your system but just takes a second to redo so you might be better off doing that.