New M1 MacBook Pros will not format the SanDisk 4TB Extreme PRO Portable SSD drives

[KDLM]

I bought two of the SanDisk 4TB Extreme PRO Portable SSD drives (that are rated at up to 2000 MB/s) and tried to format them using Disk Utility in the latest MacBook Pro with the M1 Max chip running OS Monterey 12.0.1. They both would not format. I worked with Apple tech support and we eventually resolved the problem by me formatting them using my 2017 MacBook Pro running Catalina. They formatted on that MacBook Pro with no problem and I can use them just fine on the new M1 MacBook Pro that had failed to format them. I formatted them using APFS, but they would not format in APFS or Mac OS extended Journaled on the new M1 MacBook Pro (I didn't try to format them in other configurations). Apple is already aware of this problem as is working on a fix in an update to Monterey, so this issue may already be resolved depending on when you are reading this and whether Apple comes up with a fix. For now, as long as you have an older Mac to format them on, these disks will work on the new M1 MacBook Pros.

Also worth mentioning is that you can only get read/write speeds in the neighborhood of 920/830 on this drive on any Mac, including the newest M1 MacBook Pros that have Thunderbolt 4. An Apple reviewer explained that this is true because to get 2000 MB/s your computer must "support dual-lane USB 3.2 Gen 2X2, essentially using both lanes of USB-C connectors to deliver speeds up to 20Gbps (or 2.5GB/s)."

 

[Ray2]

I had recent problems formatting 2 SanDisk ssd's on my 2018 mini under Mojave. My solution was go back to Crucial where I never experienced issues. APFS, GUID, encrypted and unencrypted. Job would start then eventually abort prior to completion.

 

[Fishrrman]

Others have discovered that "the workaround" for the disk formatting problem with the new Macs is to use a SLOWER USB2 cable instead of a USB3 cable.

Seems odd that this would work, but apparently it does.

 

[KDLM]

Others have discovered that "the workaround" for the disk formatting problem with the new Macs is to use a SLOWER USB2 cable instead of a USB3 cable.

Seems odd that this would work, but apparently it does.

That's interesting. I noticed that once I formatted these drives on my old MBP, I tried connecting them (to my new one) using an OWC Thunderbolt 4 cable, my reasoning being that it is one of the best cables on the market as it is made to TB4 standards. However, that was a mistake. It randomly dismounted two or three times in the space of 20 minutes. I then switched back to the USB-C cable it came with, and the connection is rock solid with that cable. The Apple tech rep says that isn't unusual as the manufacturers often make cables in specific ways to work better with the drives they come with. Live and learn. I don't like that because it means I always need the included cable, but there's nothing I can do about that, apparently.

 

[Clix Pix]

This has already been discussed in at least two other threads. Actually, the problem is more related to Monterey than it is to the M1 machines in particular. I bought a 4 TB SanDisk drive earlier in the month, just a short time after having updated my machines from Big Sur to Monterey. Even though I already had successfully just a few months before formatted a new 4 TB SanDisk Extreme Pro and also a 4 TB SanDisk Extreme in my 2018 (Intel) MBP running Big Sur, I found that I was experiencing errors in Disk Utility when I was attempting to do this now in Monterey. And, yes, I was using the cable with which the device had shipped. I tried the same process in my 13" 2020 M1 MBP and had the same results. Fortunately for me a friend still had Big Sur running on her MBP so I went over to her place and was able to quickly make the formatting change without any issues and the device is working fine now, just like the others.

 

[aheinz]

Others have discovered that "the workaround" for the disk formatting problem with the new Macs is to use a SLOWER USB2 cable instead of a USB3 cable.

Seems odd that this would work, but apparently it does.

I have a new 4TB Sandisk Ultra in an external USB-3 case that also did not format on my MacBook M1 Pro 2021.
Usind an old USB2 cable worked for me too.
Not a solution but still...
Have a nice day!
Arthur