Chosen Solution
Macbook Pro MId 2015 - went for a clean install after some startup issues, but The internal SDD does not mount once I get to internet Recovery and OSX install. Doesn’t mount in Disk utility either. Once in Target disk mode the disk mounts perfectly on a 2nd identical MBP. I bought a new SDD and the same problem persists, fine in target disk mode but I am unable to install OSX. Any ideas? Update (11/24/2020) Pretty sure I have wiped it clean - disk utility - erase a Mac OS journaled, GUID did I miss something here?
I’m suspecting you hadn’t fully wiped the drive. Apple has altered its new file system five times now! So you can encounter issues if you don’t delete all of the partitions and containers. You’ll need to use Disk Utility from an external bootable drive or via Target Disk Mode from your other system. create a new GUID/HFS+ volume Then run the installer. So far I’ve found setting up HFS+ is better than APFS allowing the installer to modify it.
