Crucial X9 SSD not showing up after update to Sonoma 14.3.1 - MacBook Air M2

OferFox wrote:

I'm having a similar issue. Using a Crucial X9 Pro on an M3 MacBook Air running Mac OS Sonoma 14.5. Just purchased this hard drive 2 days ago and transferred a huge amount of irreplaceable files to it. Today it started popping up input/output error messages.

I certainly hope you have a backup of this data. You should never have just a single copy of any important & unique data. In fact the more important the data, then the more backup copies you should have.

If you don't have a good backup of this data, then I highly recommend you get a good backup very quickly.

I ejected it and reconnected it and now it won't mount. Disk Utility is showing it, but it's grayed out. I'm keeping my fingers crossed that someone has some sort of solution for this, because I'd be devastated if I lost some of these files.

We don't have enough specific details about your system and this external SSD (Crucial does not make hard drives). There are so many possibilities that you really should start your own thread so that contributors do not get confused when trying to assist you. Information we need, the exact model of the MBAir (Apple menu --> About This Mac), partition & file system used on the X9, how you erased the X9 prior to using it, are you using any proprietary third party Crucial software to manage this SSD? Also, macOS configuration settings such as whether you are allowing or disallowing external drives to sleep. Plus when does this drive tend to eject? Any patterns on what is happening with the laptop when this occurs? Waking the laptop? Using certain apps? How is this external drive being used? Perhaps it is a compatibility issue with another connected device. This is why your own thread is best, but feel free to monitor this thread for any updates if the OP ever responds back here. You can also post a link to this thread as a reference to other users with a similar issue.

As an update to my previous post, I now have a 2 TB Crucial X9 SSD serving as my reliable Time Machine backup drive on Sequoia 15.0.1 on an M2 Mac mini Pro. It is directly connected to the mini. I also have a 1 TB Crucial X9 Pro being used for non-TM purposes. Both drives are formatted as APFS, and at one time, I also had the X9 Pro formatted as FAT32 without an EFI partition. In all cases, these drives purchased directly from Crucial have worked flawlessly.

I keep the version of macOS current on my Macs and those using outdated operating system versions should update to the last available, since Apple does not exhaustively detail bugs that they fix in the updates/upgrades.

I am having the same problem.

I'm getting this also. 4TB X9 Pro - Sonoma 14.5 (23F79)

When I connect the SSD it blinks slowly 3 times with the white LED, the goes on solid, but can't be read.

I am having this exact same issue. I've had this SSD for less than three weeks and have irreplaceable data as well.

Please, Does anyone have a solution to this problem?