ST2000DM001 Media won't mount
My iMac, purchased new from Apple in 2019, has been having significant problems since I installed the OS update in July. At the time, it crashed to a black screen with a white circle with a line through it. I got some help from Apple then and brought it back to life by starting in recovery mode, erasing the Macintosh HD disk, and starting fresh with a new OS download. All my data was backed up elsewhere, so that’s not an issue.
But since then, my 2TB storage has been missing. The drive ST200DM001 Media shows up in Disk Utility, but will not mount. I don’t have a great deal of computer savviness, but I think this is the root of my problem…something to do with a split fusion drive???
I recently tried erasing the Macintosh HD disk again, because it kept splitting itself into smaller and smaller bits labeled Macintosh HD - Data - Data - Data - Data - Data. Now I have a freshly reset Macintosh HD disk, a newly reinstalled OS (to the latest version available). And my iMac is still on the fritz. It keeps crashing and restarting, telling me on restart that the disk you attached was not readable by this computer. (No externals are attached...just the internal drives.)
First aid does nothing for either internal drive...comes up clean for both.
The error report on restart is attached. Relevant screen grabs are attached.
iMac 27″, macOS 12.1