Crucial X9 Pro External SSD Compatibility Problem with MacBook Pro M2 Max 2023 Sequoia 15.7.1

Si007usa wrote:

SOS!! After first use and successfully storing "critical/crucial data" on it, the Crucial X9 Pro 2TB SSD is not mounting. I have tried everything(using different cables, different Mac, different Mac OS, Windows OS, leaving the SSD connected for 10 hours) as suggested by Crucial Support and Apple Forums on the problem, but nothing seems to be working. I can't erase/reformat it either.

Sounds like the Crucial X9 has failed.

If it is under warranty, contact Crucial for a replacement.

If it is not under warranty, replace it with another external SSD.

Si007usa wrote:

SOS!! After first use and successfully storing "critical/crucial data" on it, the Crucial X9 Pro 2TB SSD is not mounting.

I can't erase/reformat it either. Error messages are as follows:

The disk X9 Pro1 can't be unlocked.

Erase process has failed.

This is very concerning. It sounds like you need to access this data, but you also attempted to erase the drive. You do realize that erasing an SSD destroys all data on it with no hope of recovering it?

The other very concerning aspect is it sounds like you don't have any other copies of this very critical/crucial data. If the data is that important, then why don't you have at least one....or better yet two backups of this drive? The more important the data....the more copies of that data you need to have.

There are several possibilities here.

1. Unable to unlock the encrypted APFS volume
2. APFS volume can be unlocked, but is unable to be mounted as read+write due to file system corruption
3. SSD issue or outright hardware failure

Unfortunately macOS & Disk Utility do not provide clear error messages to distinguish between #1 & #2. I have discovered that in most cases the volume will be unlocked, but the APFS file system is unable to be mounted as read+write. I cannot go into the steps needed to determine this at the moment, including how to attempt to mount the unlocked APFS volume as read-only without any file system checks. Way too much writing and back & forth communication is needed. I'll try to remember to get back to this thread with some details when I have a bit more time. It will involve using the command line.

In the mean time you can check the health of the Crucial SSD by running the third party app DriveDx (free trial period) and posting the complete text report here using the "Additional Text" icon which looks like a piece of paper on the forum editing toolbar. You will need to install a special USB driver in order to check the health of the external USB SSD. I'll review this report to see if the SSD is showing any types of errors that could be causing this problem, plus it will remind me to provide some instructions for narrowing down the source of the problem & attempt to mount the unlocked volume as Read-Only.

FYI, be prepared for the fact that the data on this SSD may not be recoverable even if there is nothing wrong with the SSD itself.

The X9 Pro is formatted as exFAT right out of the box and its cable is specific to its capability (USB-C 3.2 Gen 2). That cable is sufficient.

I have two 2TB X9 Pro in continuous and flawless operation as Time Machine backup drives on Sequoia and Tahoe. I do not use Time Machine encryption and the drives were formatted as APFS (case insensitive) though Time Machine will mount them as APFS (case sensitive).

APFS is not compatible with Windows whether encrypted or not, so that may have potentially damaged the drive.

If that "critical/crucial" data still exists that you put on that X9, and if you can still mount that drive on any macOS that understands APFS, you may be able to start over and reformat it as exFAT. Then mount it on Sequoia. Click once on that mounted drive and then press option+cmd+i to open a Get Info panel in front of you instead of shoving it to the upper left corner of your screen. Click the gold lock icon at the bottom and check the drive permissions and potentially check that box at the bottom: ignore ownership on this volume.

Once you are satisifed with that, close the info panel, launch Disk Utility and reformat the drive as APFS. If you really do not need encryption, skip that option and format it as APFS which will be inherently case-insensitive.

Now, copy the critical data onto the X9 Pro again.