Locked Macbook pro 2011

Hello everyone !

I have in my hands a macbook pro 2011 13", I've bought it with other macs and it is the only one giving me a headache. Long story short, it's locked and it shows the screen for a 4 digit code and under it says stolen mac report to police or call... I can return it because I know whom I've bought it from, or I can try to unlock it or sell for parts.

I opted for the second option. When I boot up the mac, if I don't press any key it takes a while and then shows the 4 digits lock screen, if I press command-r or option-command-p-r it shows me one field with a lock, and I can type anything but it takes 15 seconds to tell me if it's wrong. So at first I thought it is a efi password that I need to remove so I can boot from a usb and install a fresh macOs. Then I followed the tutorial, I dumped 3 copies of the bios chip firmware, they all matched, replaced the $SVS with FF, uploaded and verified ! Then I boot up the mac and the only thing happens is the 4 digit screen, the other one disappeared.

So my question is, when the mac is locked like that, is the tutorial I followed the right one or not? You may say do what it says ... This is a 2011 macbook, probably went through a lot of sell/buy before landing in my hands, either I unlock it and use it or return it and will go to the dump! Your help is appreciated !

Thanks.

it's locked and it shows the screen for a 4 digit code and under it says stolen mac report to police or call

That's about when I would have closed the lid and returned it or turned it over to the authorities
But that's just me

Sounds like you may not have cleared pram after the re-flash with efi cleaned.
Maybe flash it again, then upon first boot ZAP/CLEAR pram

Shut down your machine. Yes, all the way down, not sleep or logging out.
Press the power button and then press command-option-p-r. ...
Hold those keys down until your Mac reboots again and you here the startup chime.

I would hold it for a good two or three reboot chimes
Let go of the keys and let your Mac reboot normally.

Thanks for your answer,

So I've reflashed the chip, I turned on the mac and pressed the combination, but it shows me a blinking folder, there is no chime. I think the reason is because the mac didn't come with a hard drive, I had one laying around that I just formatted. So after that I turned the mac down, I plugged a usb that I use to install Sierra, when turning it on, I press the combination again but same result, except this time it shows the apple logo and loads for a couple of minutes, then it shows the 4 digit screen again.

When you zapped/cleared pram, did you hear the chime after it rebooted?
If not, you need to press & HOLD those keys until it DOES

Plug your OS usb drive in,
Power on the computer then immediately press & hold the OPTIONS key

This will force the mac into looking for bootable devices & should find your OS usb drive
If it pops up the lock screen, then you have NOT cleared the efi.

Once you do, boot onto that OS usb drive go into utilities options, and temporarily set your own efi password
format the hard drive & install OS

When I press the combination to clear the pram the mac doesn't reboot.

what does it do when you press & hold the OPTIONS key with the USB os drive install or without the usb

Without the usb it shows the blinking folder, if I plug it then it shows the lock screen.

Still a lock screen after these two steps
#1 Plug usb in
#2 Power on mac & press & hold the options key?

How was this usb drive made?

After that test,
remove usb drive, power on & press & hold R
Its best to have wifi shut off at this point if you have already connected to the wifi earlier since those setting would be retained within pram settings

Or power off, then power on & press & hold the T key
What happens?

At this point, I'm still not sure your keyboard is in working order, have a mac usb keyboard to try

Yes I still get the lock screen.
The usb was made on a MacBook air with Sierra downloaded from the app store.
The wifi is not connected because since I got the mac I never was able to unlock it.
I will test to power up + T then + R, I will edit this post when done.
I'm sure the internal keyboard is not working properly, but that's why I am use a genuine usb one.

What if I uploaded the firmware available here ? Maybe it will work better?

No don't use a donor efi just yet, As you may need to clean the ME region on that to be able to use it.

zip & upload both the locked & cleaned bin here,
I would like to compare the two

They are the same, except that the $SVS part was set to FF, and I made sure the size is exactly the same.

Booting with Option, or T, or D does the same thing, it boots to the lock screen.

after a quick look of the bins, i don't see any issues.
Since it seems you may be having issues resetting/clearing pram.
How about flash the efi again, then disconnect magsafe power adapter if connected.
Disconnect the battery from the logic board, press & hold the mac power button for 15-30 seconds. You could even try this step once prior to a re-flash of the efi chip then see if it cleared,

Remove the hard drive before you power it on any further, delete any partitions that may be on it again, don't even worry about a new format, would rather have disc utilities partition & format it anyways.

I would even re-build that Mac OS usb drive, then write protect it prior to using it

The battery is disconnected, so I don't know why the pram is still not cleared, I've done everything possible and still same issue. I will try your suggestions and will let you know Thanks f or your help!

Cyber16 wrote: Disconnect the battery from the logic board, press & hold the mac power button for 15-30 seconds. You could even try this step once prior to a re-flash of the efi chip then see if it cleared,
Remove the hard drive before you power it on any further, delete any partitions that may be on it again
re-build that Mac OS usb drive, then write protect it prior to using it

I already removed the battery, pressed the power button for more than 30 secondes, reflashed the efi chip, removed and deleted the hdd, rebuilt the mac OS usb drive, and turned on the mac.

I've pressed command R on boot, and it did same thing as before, it doesn't respond to that, shows apple logo but the only difference is this time it shows the prohibitory logo, and this is what i've found on the internet :

"When you see a circle with a slash symbol instead of the Apple logo, it means your Mac couldn't find a valid System Folder to start up from."

So I am confused, I don't have a 8.5gb dvd to try with, I know my usb is working because I've installed MBA with it.

"When you see a circle with a slash symbol instead of the Apple logo, it means your Mac couldn't find a valid System Folder to start up from."

Normally a flashing folder with a ? would means no valid OS boot found.

The circle with slash I believe mean unsupported OS ver
I very well could be mistaken

edit:
Correction:
Here is what they mean
support.apple.com/en-us/HT204156

If you have another mac that supports firewire, you could try a target mode boot onto that mac's hard rive
Or install MacOS onto the 2011 hard drive from that mac

The easiest I can do right now is this : connecting the hard drive on my pc, and using my virtual machine to install mac on it, you think it will work?

Edit :

I've done but I get the prohibitory logo again, I then reflashed the efi chip with the firmware I've downloaded (I've replaced the serial number and size matches), but same issue, prohibitory logo.

What I can't understand is why I can't boot into the Recovery mode?

So holding the "command" + "R" Keys right after power on won't give you recovery?

If not, then something else is also going on

edit:
Since you are using an external keyboard, have you tried all usb ports? maybe one not just right?
taking shots in the dark at this point

Something new happened, I've flashed the firmware I've downloaded from the efi repository, and I've rebuilt the usb, now it gives me the lock screen again, but with different message, before it was "stolen mac" ... now it is a custom message.
I think I will upload the original one (and replacing the $SVS). Maybe it will work now.

Edit :

Is there a way to know the pass code for the efi I've downloaded ?

If you downloaded it from this site repository, it should have been clean of any passwords, you would also need to modify/fill-in the serial number + possibly clean the ME region if there is still prior data in there, you could replace that data from your original dump

As I said, the one in the repository comes with a password, but I've found another one in a forum post and it worked, I was able to go into recovery mode, but there is one problem, when I click on install os it says that the drive is damaged, and I am sure it is not, could it be the ME region? Do you have any link that shows how to clean it?

And last question, I think I can access the terminal from the recovery mode, and I already saw a website that gives command to clean pram, what if I clear it then flash the original efi firmware with the $SVS cleared? Do you think it's worth the try?

Thanks a lot for your help Cyber

Edit :

I am actually installing macOS !!!!! I had to set a recent date with the Terminal then the drive damaged message disappeared, when the installation is done, I will use the Terminal to clear the pram it will be done in the next start up, I will reflash the chip with the firmware I have, and if it work then fine, if not I will reflash the last one.