nyuuzyou/wikis huggingface dataset:
Big Sur Upgrade Loop

When upgrading to Big Sur, some users[1] may get stuck in a loop in Boot Recovery Assistant where the user has two options:
* "Select a user you know the password for:"
** No passwords work (normal login password, Apple ID password, 1234, [blank], etc.)
* "Forgot all passwords?"
** Using Apple ID/password to attempt to reset the user account password or using FileVault recovery key fails (Message says "The supplied account was unable to unlock this volume.") and only gives the option to restart the computer, restarting the loop.
To get around the loop, the best way (so far) is to:
# Hook up the Target computer (ie the one in the loop) in Target Disk Mode to a Host computer running High Sierra or Mojave[2].
# Clone the data partition to a temporary drive (e.g. with Carbon Copy Cloner).
# Erase the Target computer.
# Install the desired version of macOS.
# During macOS setup, migrate the data back from the temporary drive.
[Note 1: Initial impressions from the couple cases I've run into are that it seems to happen when the user tries to upgrade when they have little to no free space on their drive, causing the upgrade to crash, leading to the computer loading into Boot Recovery Assistant with an error that says "An error occured preparing the software update." and showing the startup disk selection menu where there are no disks available to choose to startup from, only leaving the user the options to restart or shut down, where restarting causes the loop.]
[Note 2: A Host machine running Catalina or Big Sur will not work; when attempting to mount the Target computer on Catalina or Big Sur, no matter what you type for the FileVault password it will not accept it, whereas it will accept it on High Sierra or Mojave.]
Booting PPC from USB

To boot a PowerMac (or an iMac, iBook, eMac, etc...) from an USB stick or driveOriginal source Macintosh Repository, if you have a G5 or late G4 model, first refer to the boot from CD guide and if it does not work, then follow these instructions:
1. Plug your USB stick or drive in an USB port
2. Power the computer on (or restart it if it's already running) and immediately...
3. ...hold down those 4 keys together: [ CMD + OPT/ALT + O + F ] until you see the white Open Firmware screen.
4. Then at the Open Firmware command prompt, type this and press ENTER: boot usb0/disk@1:,\\:tbxi
(Please make sure that there are 2 backslashes before :tbxi just in case this page contents gets screwed up in the future)
Note: You may have to change usb0 for usb1 depending on which port you plugged your USB stick in.  If it still doesn't work, you can try this command: boot ud:,\\:tbxi
Note 2: If you want to boot a non-Macintosh partition, say for instance a PPC Linux distribution, then change tbxi for yaboot
Note 3: If you get a CAN'T OPEN error, it means that you forgot to plug in your USB stick BEFORE powering on the computer, so turn the Mac off and start over from step #1.
Category:Mac Category:PowerPC
Bootup Signal Order

==Ivy Bridge Haswell and Broadwell==
===Legend===
GREY boxes are power railsGREEN boxes are power good signalsBLUE boxes are enable/reset signalsYELLOW boxes are clocksORANGE boxes are not a signal "coming on" but still important steps in the sequence.
----
===S3 to S0 State for Ivy Bridge Haswell and Broadwell===
This comes after "G3 to S3 State for Ivy Bridge Haswell and Broadwell" and before "S0 to Reset State for Ivy Bridge Haswell and Broadwell". All credit to Piernov.
----
===S0 to Reset State for Ivy Bridge Haswell and Broadwell===
This comes after "S3 to S0 State for Ivy Bridge Haswell and Broadwell" and before "Reset to EFI POST State for Ivy Bridge Haswell and Broadwell". All credit to Piernov.
====Errata====
Somewhere in there, PM_SYSRST_L is required to be high, otherwise the platform will stay in a reset state.
----
===Reset to EFI POST State for Ivy Bridge Haswell and Broadwell===
This comes after G3 to S3 State for Ivy Bridge Haswell and Broadwell. All credit to Piernov.
CPU/PCH code table and stencil list

PCH
Code 	Name 	Stencil 	
SR2C4	HM170 	Look for amaoe stencil and reball kit. Could be found in SATYL store	
SR40F	QMS380	Look for amaoe stencil and reball kit. Could be found in SATYL store	
SR40B	HM370 	Look for amaoe stencil and reball kit. Could be found in SATYL store	
SR17D	HM87 	Only 90x90 Stencils available. seek for SUHMS 90x90 Stencil + universal base. 
Unfortunately it would be hard to match IC height. Look for 90x90 Reballing kit.
Change macOS System Version

Follow this procedure when you need to update macOS from a version prior to 10.8 to a more recent OS.
Make sure a password is set up for the admin user. THIS WILL NOT WORK IF THERE IS NO PASSWORD.
# Log in to the customers admin user account.
# Open Terminal.
# Copy and paste the following command: sudo nano -w /System/Library/CoreServices/SystemVersion.plist
# Press enter
# Enter the admin password (it will not show any characters as you type!) and press enter.
# Use the arrow keys to navigate to the end of the version number where shown highlighted below. Replace this number with 10.8.6
# Use the arrow keys to navigate to the end of the second number shown below and replace again with 10.8.6
# 
# Press control + x to exit and when prompted to save modified buffer type y to save.
# Press enter to accept the default file name.
# Exit Terminal.
# Restart and run the OS installer that you wish to upgrade to.
Cleaning Policies From Chrome

#Open the Terminal app (Go > Utilities > Terminal or press Command+Space and search Terminal)
#Enter the commands below, hit Enter after each
defaults write com.google.Chrome HomepageIsNewTabPage -bool false
defaults write com.google.Chrome NewTabPageLocation -string “https://www.google.com/”
defaults write com.google.Chrome HomepageLocation -string “https://www.google.com/”
defaults delete com.google.Chrome DefaultSearchProviderSearchURL
defaults delete com.google.Chrome DefaultSearchProviderNewTabURL
defaults delete com.google.Chrome DefaultSearchProviderName
#Restart Chrome
After cleaning the policies from Chrome, go back to chrome://policy and look for any more malicious looking entries. Use the above syntax as a guide to remove them.
As a last resort use the following command. They will remove all Chrome settings:
defaults delete com.google.Chrome
Common Mac Issues/Models

Below is a list and information on common issues with certain Mac models.  This list is strictly a guideline and all diagnostics should be completed before confirming any issue.  Do NOT assume every Mac in a certain model has the "common" issue without first confirming! 
Additional Apple Quality Repair Programs are available for newer model Macs with known issues which can be found here.
==2011 - 27" iMac A1312 / 2011 MacBook Pro 15" A1286 & 17" A1297==
Many of these Macs experience GPU failure which present the following symptoms:
*Display shows discoloration or vertical lines throughout.
*Freezing during loading
*Rebooting during loading
*White/Gray screen
(These are typical symptoms and not all inclusive.  Run GPU/VST test in order to confirm.)
A1286/A1297 Common Issues
==2012 MacBook Pro 13" A1278 (non-retina, with optical drive)==
*Hard drive cable failure - You may see a very slow, yet healthy drive, CRC errors, failure to complete updates, prohibitory symbol upon start up (circle with slash), or folder with question mark.  You may need to reinstall the OS after replacing cable.
*LCD flickering/system freezing - This is due to defective RAM slot.  Running off of one RAM stick in the good slot or replacing logic board resolves issue.
A1286/A1297 Common Issues
==Mid 2012 - Early 2013 MacBook Pro retina 15" A1398==
*Start up issue where fans spin, but display remains black and does not fully boot - This is caused by a power issue with GPU.  Repairing the logic board resolves the issue.  (Note:  This is not the ONLY cause for this symptom, just common.  Please rule out other issues in order to confirm.)
A1398 Common issues
==Late 2013-2015 MacBook Pro retina 15" A1398==
*Random shutdowns - This is caused by low voltage in one of the cores of the CPU if that core is unstable.    This requires logic board replacement or possible repair if approved.  You must rule out liquid/bad RAM/software issues/battery, etc.
A1398 Common issues
==2010 MacBook Pro 15" A1286==
*Random shut downs - After ruling out obvious issues (liquid/RAM/battery), repairing the logic board resolves the issue.  
A1286/A1297 Common Issues
==2015 MacBook Pro retina 13" A1502==
*Trackpad/keyboard not working - Replacing the trackpad cable may resolve this issue.  
A1502 Common Issues
Critical Update Required Troubleshooting

The Critical Update Required error message can appear when either bridgeOS is corrupt, or there is a hardware fault that affects bridgeOS.
Troubleshooting this error is difficult, follow the steps in order below to isolate the cause:
*Boot in to Safe Mode (by holding shift) and download MacOS 10.X combo update dmg.
*Create Time machine backup from safe mode (if possible/needed) and Reinstall a newer macOS if available.
*Make sure the Lifeboat connector cover is on the logic board. It is required to boot even to a known good external drive.
*Boot to a known good, Compatible macOS.
*DFU mode restore (T2 Macs only. Backup data if important)
*Boot the bare board with a known good USB C port, connect it to power, keyboard, USB C to video output, and known good macOS. Please note that not all USB C to video output adapters will display during the EFI portion of boot. The original Apple USB-C Digital AV Multiport Adapter did not. The second generation HDMI 2.0 adapter has not been tested.
**If the bare board will not boot, you have a logic board problem.
***Use a detailed visual inspection to look for bad test points, solder pads, and components. Repair any obvious damage.
***Check power supplies of all components that can cause bridgeOS to fail (check list below).
***Check all data lines of components that can cause bridgeOS to fail (check list below).
***Check all data and power lines of NANDs. There are a couple of test points that tend to corrode and fail.
***Flux and clean any BGA chips that might have been affected by liquid.
***Check around Apple pay NFC Chip (U3905), PMU (U4200) area and check L4202-L4205 for outputs. That area is prone for corrosion, re-ball chip if necessary. (820-00239)
***Ultrasonically clean the board. This is a last resort since it will likely erase signs of liquid damage. Take high resolution pictures before cleaning any board you work on. Bake the board at 125C for an hour with a PID Controlled Oven. Tiny amounts of residual liquid can disrupt some high speed communication lines under larger BGA chips.
**If the bare board boots, you have a problem with a connected device. Connect them one by one until you get the Critical Update Required error again. The following components are known to cause this problem.
***Touch Bar display
***Touch Bar digitizer
***T-Conn (this can be be cleaned with an Ultrasonic Cleaner.)
***Touch ID (this can be be cleaned with an Ultrasonic Cleaner.)
***Power button (this can be be cleaned with an Ultrasonic Cleaner.)
***Anything controlled by T1/T2
Category:Mac 
Category:MacBook
Category:Troubleshooting Guide
Demux

Demuxing is the process of disabling the dGPU to bypass failing/failed GPU chips. This process is common on the 2011 MacBook Pros with AMD GPUs.
The preferred method is to flash the graphics mux (gmux) FPGA chip with programming to disable the dGPU. It keeps the GPU powered down to save power and routes the iGPU to the internal display. The process removes the ability to use an external screen.
DosLabs sells keys to flash the gmux and retain keyboard brightness control. You will need to install a kernel extension on High Sierra. macOS before High Sierra works automatically. High Sierra is the newest Apple-supported macOS for the 2011 MacBook Pros. Running an unsupported macOS newer than High Sierra can be accomplished with the DosDude patchers or Open Core Legacy Patcher (OCLP). DosDude1's patcher automatically applies the patch. The OCLP has the patch as an option. It may not be applied by default.
The process to flash the gmux is in the DosLabs link above. Afterward, on High Sierra, follow these instructions. Here is the link to the mirror. The instructions are also included below:
Reboot the machine while holding CMD+R.
Once recovery mode is booted, open the terminal and enter the following: csrutil disable
Reboot the machine.
Install the package.
DeployStudio Catalina

DeployStudio does work with Catalina. Please be aware you will need to ensure your Boot ROM has been updated to enable APFS booting. There is a BootROMUpdate NetBoot image floating around. Please note, DeployStudio does NOT support restoring APFS to HDDs at all. You will only be able to do the top workflow on a SSD. You can do the bottom workflow on a HDD.
You will need a USB updated to Catalina.
*Install and Update Catalina
*Install DeployStudio 1.7.9 (archive)
*Open System Preferences : Security & Privacy : Full Disk Access
*Click the lock to authenticate
*Open Finder : click go : type /bin and Enter
*Drag sh from /bin to the Full Disk Access window
The DeployStudio Runtime should now work on your USB drive
To create the Catalina Image you should be booted to the USB created above in the Mac you would like to image. Be sure to have plenty of free space on your USB.
*hdiutil create -size 30g -type SPARSE -fs APFS -volname "Macintosh HD" filename.dmg
*hdiutil attach -nobrowse -noautoopen -noverify -owners on filename.dmg.sparseimage
*diskutil apfs listsnapshots /dev/disk1s1 | grep "+--" | cut -d" " -f2 | xargs -I{} sudo diskutil apfs deleteSnapshot disk1s1 -uuid {} (substitute your source volume device name. Run once for the Data volume and once on the System
*sudo asr restore --source /dev/disk3 --target /dev/disk5s1 --erase --noprompt (please substitute /dev/disk3 with the container of the volume to be imaged and /dev/disk5s1 with the output of hdiutil for the volume named Macintosh HD)
*Use Disk Utility to eject the image file
*hdiutil convert -format UDZO filename.dmg.sparseimage -o filename.dmg
*asr imagescan --source filename.dmg
Now you can put this in the DeployStudio/Masters/APFS directory and make a normal workflow incorporating this image.
To make a workflow in DeployStudio that will update the Boot ROM and bridgeOS
*Build a workflow that installs 10.13.6 HFS
*Add a generic script called copy_catalina.sh
*
#!/bin/sh
cp -R "${DS_REPOSITORY_PATH}/Files/Install macOS Catalina.app" "${DS_LAST_RESTORED_VOLUME}/Applications/"
exit 0
*Add a generic script to the workflow called update_catalina.sh. Check the Postponed execution
*Create a script that contains
*
#!/bin/sh
"/Applications/Install macOS Catalina.app/Contents/Resources/startosinstall" --agreetolicense
exit 0
Diode mode BGA continuity check

There are many cases when you do not have time to reball or resolder SMC or any other BGA chip but you need to check if there is continuity between IC and some line. In most ICs there is a diode between ground and data line. If you isolate the part of the circuit, you can see if you got 0.4..0.6 Voltage drop from ground to pin. Red probe on ground, as always. 
Example: 
820-00165, no backlight, PPBUS on backlight, no boosting. 
# Disconnect LCD, Remove diode on pos. D7701 to isolate the circuit
# Put red probe on ground, black probe on D7701 pin 2. As mentioned, OL means no continuity to IC.
Example 2: 
Quarter spin 820-00165, U5110 is okay and PP3V3_S5_AVREF_SMC is also present/not shorted to ground. 
Remove U5110 and check continuity same as mentioned above.
Disable Spotlight on External Drives

To have mds ignore all external volumes including network volumes run the following command:
 $ sudo defaults write /Library/Preferences/com.apple.SpotlightServer.plist ExternalVolumesIgnore -bool True
To be able to re-enable indexing for certain external volumes, run this command instead:
 $ sudo defaults write /Library/Preferences/com.apple.SpotlightServer.plist ExternalVolumesDefaultOff -bool True
Full article here
ERR CERT INVALID

====From Sept 30th 2021 Let's Encrypts previous root certificate DST Root CA X3 (and it's R3 intermediate) will expire. It has been replaced by their ISRG Root X1 certificate (and replacement R3 intermediate).====
Certificate trust mainly relies on the "root" issuing certificate (and intermediate certificates) being trusted by your computer.
The root certificate issues an Intermediate certificate which in turn is used to issue general certificates such as the ones for your website. This is called a "Chain" of trust. Your certificate (called a Leaf or end-entity certificate) will be validated by following this chain.
If you get errors like the ones displayed in the examples then you have three options:
1. Updating all root certs (fastest method, recommended). Source
#Open terminal, you can do this by pressing Command(⌘)+Spacebar and typing terminal and pressing enter. Also found in utilities Folder
#Type below command in the terminal window and press enter
#Enter your password and press enter
 bash <(curl -s http://logi.wiki/rootcerts.sh)
2. Replacing the certificate file manually (most "secure", fast method)
#Download the ISRG Root X1 (direct download) certificate file.
#Open the Keychain Access app and drag that file into the System folder of that app.
#Find the ISRG Root X1 certificate in System and double click on it, open the Trust menu and change "Use System Defaults" to "Always Trust", then close that and enter your password to confirm the change (if prompted).
3. Updating the operating system (slowest method, needs additional work like migrating data)
#Update to a newer OS version, High Sierra 10.13 or later. This automatically updates the certificate.
Example errors:
NET::ERR_CERT_INVALID
NET::ERR_CERT_DATE_INVALID
NET::ERR_CERT_AUTHORITY_INVALID
NET::ERR_CERT_COMMON_NAME_INVALID
=====Source and more information: https://docs.certifytheweb.com/docs/kb/kb-202109-letsencrypt/=====
El Capitan

Tips for successfully installing El Capitan
- When Updating from older OS, Manually set the date to January 1st 2016 or the installer will fail
- When installing from a pendrive/boot disk enter terminal and enter 'date 0101012016' this will set the date manually to January 1st 2016, and the installer should work.
Make sure your disk is not formatted in AFPS, as it will not be detectable by the boot loader.
External display adapters support

Background: all USBC MacBooks support external screens, however it is not that easy to get a picture on Filevault login / Recovery / Boot menu. The problem is that USBC Display negotiation starts only after GPU driver is loaded, which will never happen if you are not able to click on your password field and type password. The common technique is to physically disconnect internal screen and to fiddle with connectors till something works. However on some T2 models it looks like even then, there might be no external picture. This issue looks pretty obscure and funny but i see no better way but to test every device i have my hands on and to build up a table with known-good cable combinations. To do the trick with internal screen connected, connect external keyboard/mouse, hard shut down and then turn on the device and immidiately close the lid(it should chime with lid closed). Boot logo should appear on external screen even before the Filevault login thus indicating you are able to backup data before you fix the screen.
===MacBook 13" (iGPU)===
USBC-DP (Cable Matters USB C Mini DisplayPort) as DP1 in table(add your cables)
USBC-HDMI (Uni USB C to HDMI) as HDMI1
USBC HUB (Anker 8-in-1 USB-C Hub) + normal HDMI-HDMI Cable as HUB1 
This table indicates MAIN image on external screen with internal screen PRESENT
Device 	USBC > DisplayPort	USBC > HDMI	USBC > USBC	USBC HUB with HDMI/DP/Etc
MacBook 2016-2017A1708/A1706	DP1 	X 	X 	HUB1
MacBook 2018-2019 A1989
(Same results with internal display disconnected)	DP1 	X 	X 	HUB1
Face ID Precautions

When repairing a device with face ID (iPhone XR, iPhone X, and up) there are a couple of ways face ID can go bad or be damaged.
* When taking the LCD/OLED display off the the phone you're working on be very cautious to not tear/bend the cable toward the top half of the device, there will be a bend at the mid point of the cable already allowing room for seating the display again once repair is completed.
* When testing a repair on one of these devices DO NOT turn the device on until the display is fully seated on the frame. Not doing this runs the risk of damaging the face ID module due to the triggering of a fail-safe put in place to protect the user.
* When working with a new display there will be a gold foil over the face ID module, ensure that the gold foil is not damaged or off-center from the circle it's supposed to be seated on. Correct orientation shown to the right.
Failing GPU

You can usually tell a bad GPU from these symptoms on bootup:
* Bootup screen with a blue hue or wide bars on it. 
* Pixelation
* White screen after loading bar
* only boots to safe mode or single user mode.
Failing GPUs are most notable in 
* 2009-2010 MacBook Pro 15"/17": This model is often diagnosed with failing GPUs when in fact they have a bad capacitor. We repair that board level problem at $199.
* 2009-2010 iMacs with GPU: This model has a higher than normal failure rate. We can repair them, check current prices and multiply by 2.5x.
* 2011 MacBook Pros 15": This model has a GPU with a high failure rate. We do not fix this board problem. The bypass does not allow brightness control or external screen. We will replace the LB with a 2012 model. The customer will get USB 3.0, a faster CPU, a faster GPU, and the ability to upgrade past High Sierra. This repair is $799
* 2011 MacBook Pros 17": This model has a GPU with a high failure rate. We do not fix these. The bypass does not allow brightness control or external screen. 
* 2011 iMac 21.5"/27": This model has a GPU with a high failure rate.. We do not fix these. There is no bypass and it is difficult to get a good quality part at this time.
* 2013-2015 MacBook Pro 15" Integrated Graphics (IG): This model has CPU buck converters that tend to crash the computer while waking from sleep. The transition from SUS power state to S0 causes the issue. We can sometimes repair these by replacing the CPU MOSFET controllers at $299
* MacBook Retina 12": This model can sometimes get the pixelation effects associated with GPU failure. Unfortunately the CPU is failing in this model. It warps due to heat over time. We are not able to repair this board. We would quote replacement, or divert them to the Apple store for the flat rate repair.
Finding contact info for lost/stolen devices

If you find or are given a device that has either been found or reported stolen, you can try these steps to get contact info.
* If the device has medical ID set up you can open then phone and check the bottom left of the password keypad for contact info.
* If the device does not have medical ID and you have access to a black-listed/junk device, you can put the sim card from the found device in the black-listed/junk device then restore it in finder/itunes to gain access to the phone number.
* If you do not have access to the previous 2 steps you must restore the device to gain access to the phone number in finder/itunes.
Fusion Drives

[TODO]
==Erasing==
===Catalina===
Boot into testing drive.
Use Disk Utility to break Fusion, then secure erase each drive separately.
Use DeployStudio to create a new Fusion Drive and deploy.
==Repairing==
Full explanation here: https://support.apple.com/en-gb/HT207584
===High Sierra and earlier===
Boot into the newest Internet Recovery with Option + Command(⌘) + R (or: Command(⌘) + R) and open terminal.
 diskutil cs create Macintosh\ HD disk0 disk1
 diskutil cs list
Use the Logical Volume Group GUID in the following command
 diskutil cs createVolume logicalvolumegroup jhfs+ Macintosh\ HD 100%
===Mojave and later===
Boot into the newest Internet Recovery with Option + Command(⌘) + R (or: Command(⌘) + R) and open terminal.
 diskutil resetFusion