Volume Hash Mismatch

[- rob -]

I wanted to draw attention to a problem in MacOS Monterey called “Volume Hash Mismatch.”

This has been discussed at length in the hackintosh thread, but it is a real problem affecting genuine macs too.

I encountered this unexpectedly one morning this past week on my 2018 Mac Mini. The machine has been stable for years.

There are threads showing that this has been a problem going back to the betas for Monterey, but I can say for certain it persists through 12.2.1.

Here is one from developers.apple.com:

Volume Hash Mismatch | Apple Developer Forums

developer.apple.com

(Starts at Monterey beta, but continues through 12.2.1)

One on the normal public forums:

Volume Hash Mismatch? - Apple Community

discussions.apple.com

I did initial troubleshooting with Apple support including safe mode and OS reinstall from recovery mode. Both failed. There are people in the above threads that have gone much further and essentially given up on their macs as broken.

This includes both Intel based and new, M1 Pro machines.

I just found out that my Mac Mae is still covered by AppleCare plus, so I’m going to take it to a store and let them hold onto the machine and fix it themselves.

Given the amount of discussion on apple.com on a little surprised there aren’t more remarks about it here.

So here is a thread. I’ll update it with whatever resolution I come to.

 

[jayfromnova]

Still happens in 12.3 as well. Rebuilt my 2015 MacBook Pro about 2 months ago and it just happened again.

 

[Jack Neill]

Ive been getting a few times a week on my iMac 14,1 running 12.3. It doesn't seem to affect anything other than an an annoying notification.

 

[- rob -]

Ive been getting a few times a week on my iMac 14,1 running 12.3. It doesn't seem to affect anything other than an an annoying notification.

Do you have a spare USB drive hanging around? I meant to post, but I made the bootable USB for memtest86 and was able to determine my 64gb of Crucial memory had serious errors.

I have an RMA ongoing to replace the ram and am using some temporary ram now that passes memtest86 just fine and has no issues.

I believe Monterey is or has become much more sensitive to RAM errors.

If possible please consider making the USB drive, changing your boot setup and running The test: https://www.memtest86.com/download.htm

 

[WeatherWeasel]

I just got a flash on that as well. I am not going to re install the osx. I am guessing it is one of those bugs that with the next update it will be fixed. I did notice that i had the volume on my imac turned off and maybe that had something to do with it.

I really do not want a new mac or have the time to take mine into the shop to be re done. I need it daily and yada, yada. I have backup, I have all that.

So just wondering what happens if I never see that again..

 

[minik]

I noticed this warning message on both 2017-era 5K iMac and 13-inch MacBook Pro after updated to macOS Monterey 12.5. Ran the memtest86 and they all failed. No aftermarket RAM module on the 5K iMac, I remember having trouble applying the minor update of macOS Monterey in the past especially having Sophos Anti-virus installed (it's a work computer).

 

[kibepo73]

Well, it’s not clear yet what actually causes the hash mismatch error in macOS, as users have reported it randomly appearing, or after a significant system crash or kernel panic. However, whenever a user experience this error message, it’s a good idea to immediately backup all data on the Mac with Time Machine or any other backup method of choice.

Further, the user can also try the below troubleshooting methods to fix the issue:

1. Reset SMC
2. Reset PRAM/NVRAM
3. Reinstall macOS

Hope this will help!

 

[entwerfen]

My iMac Pro had that volume hash mismatch warning pop up yesterday. Within a few seconds it completely died. Will not startup, no power at all. It’s in for service now, should hear back on Tuesday.

 

[minik]

My iMac Pro had that volume hash mismatch warning pop up yesterday. Within a few seconds it completely died. Will not startup, no power at all. It’s in for service now, should hear back on Tuesday.

I had an iMac Pro at work that no longer power up as well. Since it's not my computer, I had no idea how it happened. Hope you have the data backup somewhere else.

 

[entwerfen]

I had an iMac Pro at work that no longer power up as well. Since it's not my computer, I had no idea how it happened. Hope you have the data backup somewhere else.

Yes I do. I can't imagine the feeling of losing all that stuff without a backup.

This has made me rethink how I store files. As a freelance art director I've always kept project files on an external drive with a Synology and cloud backup. Personal files and the system backed up to Time Machine. The personal files will now go external too, it just easier to manage in situations like this.

I have an old MacPro 5,1 as a backup box. It was setup, but you never REALLY have it setup to fully go to work on a moments notice. It took an hour or so to get the settings in a place where I could get stuff done again. I may have to get a Mini/Air to keep the same software versions available on a backup Mac for the next time something like this happens (and it will). Complacency creeps up on you.

 

[minik]

Yes I do. I can't imagine the feeling of losing all that stuff without a backup.

This has made me rethink how I store files. As a freelance art director I've always kept project files on an external drive with a Synology and cloud backup. Personal files and the system backed up to Time Machine. The personal files will now go external too, it just easier to manage in situations like this.

I have an old MacPro 5,1 as a backup box. It was setup, but you never REALLY have it setup to fully go to work on a moments notice. It took an hour or so to get the settings in a place where I could get stuff done again. I may have to get a Mini/Air to keep the same software versions available on a backup Mac for the next time something like this happens (and it will). Complacency creeps up on you.

For sure in your case, personally I have a Synology NAS and Backblaze. With the iMac Pro, I believe it has two raw Flash storage chips. Adding T2 chip into the mix, data recovery may be zero once the Flash storage moved away from the logic board.

 

[FNH15]

Had this pop up on a 2016 MacBook Pro 15” that I manage.
Hopefully a SMC / PRAM reset will fix it.

It’s not economical to repair that machine, and there isn’t a direct replacement either (the 16” MacBook Pro is much heavier than that model).

 

[entwerfen]

For sure in your case, personally I have a Synology NAS and Backblaze. With the iMac Pro, I believe it has two raw Flash storage chips. Adding T2 chip into the mix, data recovery may be zero once the Flash storage moved away from the logic board.

I miss the days when you could just carbon copy clone a boot drive and slap it into another MacPro and go. The T2 changed that...

 

[minik]

I miss the days when you could just carbon copy clone a boot drive and slap it into another MacPro and go. The T2 changed that...

I use CCC at least once a year. We have stolen/missing laptops here and the built-in T2 chip feature set is sure very nice

 

[FNH15]

Had this pop up on a 2016 MacBook Pro 15” that I manage.
Hopefully a SMC / PRAM reset will fix it.

It’s not economical to repair that machine, and there isn’t a direct replacement either (the 16” MacBook Pro is much heavier than that model).

Closing the loop on this:
Ran memtest86 on the machine, threw up a bunch of errors relating to RAM. AHT also mentioned a defective memory module.

Replaced with a 16” MBP and AppleCare.

 

[rehkram]

There are threads showing that this has been a problem going back to the betas for Monterey, but I can say for certain it persists through 12.2.1.

Actually it started popping up in Big Sur. I seem to recall getting it in Catalina as well which was still supported, but at that time I was preparing to upgrade the SSD to a bigger one and to clean install macOS.

I believe it's a spurious error message. Well maybe not if it's associated with Macs failing to restart. Does anyone have any direct evidence that the Macs that fail to restart after receiving that message are anything more than a coincidence?

I just dismiss the message and, so far, eventually it stops reoccurring. I put it down to bad exception handling somewhere in the stack, along the lines of Microsoft's "Error nnnnnn - An error occurred". Lazy programming in other words.

 

[FNH15]

Actually it started popping up in Big Sur. I seem to recall getting it in Catalina as well which was still supported, but at that time I was preparing to upgrade the SSD to a bigger one and to clean install macOS.

I believe it's a spurious error message. Well maybe not if it's associated with Macs failing to restart. Does anyone have any direct evidence that the Macs that fail to restart after receiving that message are anything more than a coincidence?

I just dismiss the message and, so far, eventually it stops reoccurring. I put it down to bad exception handling somewhere in the stack, along the lines of Microsoft's "Error nnnnnn - An error occurred". Lazy programming in other words.

I’d heed the warning. It has to do with the way Big Sur and Monterey handle booting & checking against the RAMdisk (the “cached” memory).
I’d suspect that if you ran memtest on the machine in question it would pop up with memory issues. AHT also logged a bad memory module as well.

My machine that was affected booted fine, but its in a mission critical production environment where downtime = $$$$. If you are in a different scenario and aren’t as concerned about data integrity / reliability, YYMV.

 

[rehkram]

Thanks, but in the absence of any real proof of a problem, and the fact it hasn't thrown this error for at least nine months, I will continue onwards.

 

[FNH15]

Thanks, but in the absence of any real proof of a problem, and the fact it hasn't thrown this error for at least nine months, I will continue onwards.

Obviously your choice. Can’t hurt to run memtest though…

 

[entwerfen]

Not much new on my iMac Pro. They know the power supply is toast. When they get the part in, they'll test the mainboard, memory and ssd. They can't give me an ETA right now, so I ordered a Mac Studio to keep the work moving. If the iMac is totally cooked I may try the DIY 5k monitor mod, or sell it for parts. If it's a reasonable fix, I'll sell it to a friend.

I didn't really want to go M1 just yet, I have a few Windows VMs, but it doesn't make sense to buy a new Intel box and there's no used bargains in my area.

 

[minik]

Not much new on my iMac Pro. They know the power supply is toast. When they get the part in, they'll test the mainboard, memory and ssd. They can't give me an ETA right now, so I ordered a Mac Studio to keep the work moving. If the iMac is totally cooked I may try the DIY 5k monitor mod, or sell it for parts. If it's a reasonable fix, I'll sell it to a friend.

I didn't really want to go M1 just yet, I have a few Windows VMs, but it doesn't make sense to buy a new Intel box and there's no used bargains in my area.

I wonder if it's common for the short-life power supply in the iMac Pro.

 

[entwerfen]

Update. Almost everything is bad: logic board, ssd, ram, power supply - the screen is fine. Quoting $2,600 to fix (No thanks). I’ve owned around 30 different Macs since 1986, with this only two have totally failed. A few have been running great for decades, so I guess I was due.

I received my new Studio and Studio Display today. The monitor was DOA. My luck continues.

 

[minik]

Update. Almost everything is bad: logic board, ssd, ram, power supply - the screen is fine. Quoting $2,600 to fix (No thanks). I’ve owned around 30 different Macs since 1986, with this only two have totally failed. A few have been running great for decades, so I guess I was due.

I received my new Studio and Studio Display today. The monitor was DOA. My luck continues.

That's a lot. I wonder if it's the hot Intel Xeon processor that led to the problem. Sorry about the DOA Apple Studio Display, at least you don't have to wait 8-10 weeks (like I did) for it to ship.

 

[Engender]

I just got the error after I tried to open Music and Music crashed. MacOS is on a NVME drive and my music folder is on a HDD. I don't know if that has anything to do with anything, but.

 

[Kidguitar]

Installed Ventura on iMac 2019, still have problem. Turning off bluetooth as per Mac forum. Fingers crossed