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Downgrading or upgrading to a no longer current version of iOS is generally not possible once Apple stops signing the old software, as is needed when iTunes is preparing to install or restore an iOS. This signing window typically is closed within days of a new version shipping. Putting a newer iOS on older hardware that never even supported that OS is near ...


37

Note: There is a new method of downgrading/upgrading that doesn't require Apple to be currently signing, and it works on newer devices that aren't present in the first list of my answer below. The tool for it is called futurerestore (codenamed Prometheus). The biggest caveat to this tool is that you must be jailbroken in most cases before initiating the ...


10

What could have caused this? The macOS Sierra 10.12.5 beta (and the 10.12.4 beta before it) included an eficheck tool. This tool is designed to verify your EFI firmware by reading data from the Serial Peripheral Interface (SPI) flash and verifying its signature is valid (i.e. it hasn't been tampered with). Basically it's doing this to prevent system ...


7

Yes, 3.7.2 is the current version. Source: https://discussions.apple.com/thread/8414325


5

The closest equivalent is holding option at start. That runs the firmware that allows you to select network boot or external or internal bootable OS. There is no open firmware anymore where you can enter commands, so you can just reset NVRAM or let the option boot read the current NVRAM settings. Anything you would set in bios, you can write to the non ...


5

It is necessary to obtain the installer application for macOS High Sierra. Once that is available in /Applications one can use the following script to extract the firmware data and install scripts to produce a standalone firmware installer package: #!/bin/sh # Based on investigations and work by Pepijn Bruienne # Expects a single /Applications/Install macOS ...


4

The IPSW file type is primarily associated with 'iPhone/iPod' by Apple Inc.. This is a firmware update file for the iPhone. The file is a renamed .ZIP file. If you unZIP it you will see a file called MANIFEST.PLIST and a file without an extension but with a version number in the name, e.g., Firmware-14.5.3. This file is the firmware image. Source http://...


4

Currently there is no way to jailbreak either an Airport Extreme or a Time Capsule. Whilst they are probably in the same order of difficulty as jailbreaking as say an iOS device, no one has really spent any effort on doing so. Personally I think this is probably for the following reasons: limited target audience (low numbers of product in the world) ...


4

First check your current Firmware and SMC version About your Mac -> More -> System Report. Check the Boot ROM and the SMC version. It should look similar to this: The latest Boot ROM version for your MacBookPro8,1 (Early 2011) is MBP81.0047.B2A and the latest SMC version 1.69f4 (SMC 1.7). If you get the same versions the latest EFI updates are already ...


4

Long Version: The code which permits Internet Recovery Mode (i.e. a slightly modified TFTP client) is stored in the computer's firmware. (In fact, it is a part of it). It's similar to the BIOS chip on Windows computers. When you boot through Internet Recovery, it will download a recovery partition image and load it into the computer's RAM. After this process,...


4

The EFI partition is used when the firmware is updated. I assume this EFI partition must be on the primary internal disk. Apple posted that firmware updates require a GUID partition scheme at the archived website Firmware updates for Intel-based Macs require a GUID partition scheme, although the site does not explicitly say this must be the primary drive. ...


3

Right click on update - Hide update.


3

You should know there is no such this as "BIOS" on a Mac (the equivalent system is called EFI, but you don't boot into it to change settings). To boot from a DVD or any other external medium, you'll have to hold down the Option ⌥ key while booting. Then you'll get a list with all the bootable devices and there you can select the device you want to boot from. ...


3

The line panic-info is the details of the last kernel panic registered and stored by the system. If you do a PRAM (or NVRAM) reset, those details will be removed. For example, I just ran nvram -p and I had no panic-info line because I did a PRAM reset since my last kernel panic. I can't even remember the last time I had a kernel panic. Hope that clears ...


3

The official answer to this is no, you can not restore to a previous version of iOS other than the current one available from Apple. This is because iTunes is attempting to obtain tokens from the Apple signing servers to authorize the device when restoring. The non official answer is yes, but requires some technical skills using iFaith. Post back if you ...


3

A fresh OS install won't reset the hardware, SMC or PRAM. It might be well worth checking both those are correctly reset before going so far as a wipe & install. Reset the PRAM first - hold Cmd/Opt/P/R at the chimes & wait for the chimes to happen a second time. SMC varies per machine, Mac Pro is sufficient to power off & leave the mains plug ...


3

Your only option is to visit an Apple Authorized Service Provider (AASP) or one of their Genius Bars. The process to bypass a firmware lock changed a few years ago and now requires that a certified technician (ACMT) contact Apple with the Mac's information, which Apple will then process and use to remove the firmware lock. You can find a list of AASPs ...


3

You can't restore out of this problem, even with DFU restore. A bug with 64-bit devices renders them ‘bricked’ if you set the date to 1970-1-1. Take your device to an Apple Store for them to reseat the battery, or you can try reseating the battery yourself. You could also put it in a drawer and eventually the battery will drain to a point where the date ...


3

Do MacBook devices have something [firmware] similar? Yes. It's call the EFI or Extensible Firmware Interface Is it possible to reinstall MacBook firmware? Yes. See this post: Where is the EFI stored on the macbook and is it possible to restore a previous EFI firmware version? Is the firmware automatically reinstalled upon an OS reinstallation? ...


3

Just wanted to post on this topic since I had a related problem in an Apple store yesterday and this was the post I found. Apple had replaced my logic board but didn't install the newer firmware and so I could no longer boot off of my existing SSD drive (which was formatted with APFS, and had my original Mojave and all of my files). Luckily one of the ...


3

No, it is not possible, so it doesn't make sense and hasn't been done before. Yes, the hardware is different (considerably). It's a completely different board and layout where the CPU and RAM are. The difference on the cases is around the FireWire 400 ports. The 1,1 could be flashed to 2,1, and the 4,1 to 5,1; that mainly buys you newer CPU support (well, ...


3

Installing the full "Install macOS High Sierra" app over again will re-apply the firmware update, whether or not it was done previously. Installing 'over the top' in this manner will leave all your data intact. As an added bonus, it will add or fix the Recovery Partition too.


3

The panic report you posted in your previous question indicates an unrecoverable error in the IOAcceleratorFamily kext while trying to communicate with the NVDAResman kext. This indicates a problem with the GPU, probably related to the weird firmware update you applied. I think you're out of luck at this point. Only Nvidia has software to downgrade a GPU ...


2

My understanding is only Cydia. Everything that changes the phone via jailbreak comes in via Cydia. :)


2

To answer some of your questions: The firmware is stored on main board. However, when updating firmware, the EFI system partition is used as a staging area. After serval testings, it seems that Mac only recognizes the EFI partition at primary internal disk as a staging area (note: at least not working at the optical bay of my mac or at any external drive). ...


2

Firmware update and FileVault A forum post suggests that Firmware updates require access to /System/... in addition to the EFI partition (disk0s1). Since /System/... is located on the startup volume it is encrypted if you have FileVault 2 enabled - due to Full Disk Encryption. If you search further down in /System/... you will find the Revision number ...


2

Using the Intel power gadget (above) shows your CPU running at low speed. In normal case that would be fine if there is no load. I have MBA with 1.8 GHz Intel Core i5 and runs at 0.85 at normal use, how ever it does spikes to 1.8 + under load. Since the computer processing speed depends on more than one factor (CPU +SSD read/Write+RAM)... I would say you ...


2

system_profiler SPSerialATADataType | awk '/Revision/ { print $2 }' That should get you the current firmware version of your SSD. TPVABBF0 = has update TPSABBF0 = does not have update


2

EFI firmware updates are 'staged' in the normally hidden EFI partition on your disk, which typically resides at device /dev/disk0s1. Once in single-user mode, you can create a folder in which to mount this partition, then mount it like so: mkdir /Volumes/efi mount -t msdos /dev/disk0s1 /Volumes/efi From here, navigate into the /EFI/APPLE/FIRMWARE/ sub-...


2

The Mac equivalent of a UDID is a Serial Number. It can be found by click "About This Mac" in the  menu, and clicking twice on the version number.


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