Trying to resurrect an older MBP and I'm at my wit's end on how to go about it. Hoping you all might be able to shed a helpful light on things.
The MBP in question is circa 2012 and immediately boots to the OS X Base System on startup. When going through the 'Reinstall Max OSX' option (High Sierra, in this instance) I'm able to proceed past the license agreement but lack any disk volumes besides the Base System (which I clearly can't override). Additionally, the base system itself seems to take up roughly 350 GB of the total 500 GB hard drive.
When moving through Disk Utility options I am only able to run a First Aid check or Partition both the OS X Base System and the internal Hard Drive (a Toshiba MK5065GSXF HDD). When attempting to partition I have no option to increase the number of partitions. Additionally, the OS X Base System now registers as being 500 GB in size in this menu.
So,long story short--the hard drive seems borked. If anyone has any ideas on what I might try next, I'm all ears. Otherwise, this little dinosaur may end up being recycled.