Unable to rename AppleThunderboltNHI.kext in recovery mode on Monterrey 12.7.6

Lowlandsbear wrote:

My aging Macbook Pro (Retina, 13-inch, Early 2015) running under Monterrey (Version 12.7.6) has recently developed a habit of spontaneously switching off.

[Re-Titled by Moderator]

Original Title: AppleThunderboltNHI.kext

?

That is crazy talk— you do not have r/w permission on System files. You have fallen into some rabbit hole.

/System/Library/Extensions/AppleThunderboltNHI.kext

To trouble shoot further you can:

—A SafeBoot Start up your Mac in safe mode - Apple Support will sort many anomalies

Does a quick disk repair before it fully boots up, and certain system caches get cleared and rebuilt, third party system modifications and system accelerations are disabled temporarily.

Login and test. Reboot as normal and test. Caches get rebuilt automatically.

This test will tell you if third party interference; most extensions etc are not loaded in safe boot mode.

—Test issue in another user (or guest user) account Change Users & Groups settings on Mac - Apple Support

This will tell you if it a universal issue or isolated to your user/admin account. 

***wireless keyboard with rechargeable batteries— connect the charging cable, this will make the wired keyboard successful Safe Boot your Mac.

unplug all non-essential peripherals when testing

Uninstall all third party apps that are Cleaners/Optimizers/VPN/Anti-Virus

all known to cause issues on the macOS

In or out of warranty you can get a free over the counter 'Apple Service Diagnostics' test /assessment

Make an appointment for a "hardware issue"

Genius Bar Reservation and Apple Support Options - Apple

Outside the USA

Contact Apple Support - Apple Support

see vintage and obsolete:

Obtaining service for your Apple product after an expired warranty - Apple Support

Obtaining service for your Apple product after an expired ...

<< A search on online forums has taught me AppleThunderboltNHI.kext is the most likely culprit. >>

Macintosh systems are unbelievably complex. What other people decided was the issue has no bearing on what you are experiencing. They may have completely different issues from yours, especially if the issue is as amorphous as shutting off.

Consider downloading and running this little "discovery" utility, Etrecheck. It changes NOTHING. Etrecheck was developed by a senior contributor here, and uses mostly system calls and simple tests to collect often-needed information.

it contains little tests for speeds of devices, CPU utilization, memory usage, energy usage and a digest of recent problems, in one easy to use package. it does not even need to be Installed. Because less can be learned when your Mac is running great, best time to run is when your problems are actually occurring, if possible.

if you follow the directions faithfully, its report (pre-laundered of all personally-identifiable information) can be "Shared" to the System ClipBoard, then Pasted into an ‘Additional Text’ window in a reply on the forums.

Use Etrecheck Pro for free:

http://Etrecheck.com

The amount of data you get can be daunting. If you POST your report, some Readers here are willing to look over those reports, and can provide valuable insights.

then start a reply on the forums, click the "additional text" icon, and PASTE