date 1116211618
What was your last OSX installed on the Mini? If your last OSX was either Catalina, Mojave or High Sierra, then it's more likely that the internal drive was formatted APFS. This would explain why you have 2 partitions. APFS will have 2 and 1 of them can not be unmounted. Also, it's more than likely that your boot firmware on the Mini was updated as well, which means it changes the boot up parameters. The new boot firmware puts 1st boot priority on Thunderbolt and Firewire drives, network boot and the least so with USB key drive, unless it has the right boot firmware that allows secondary boot up from a USB port. Lack of Thunderbolt or Firewire drives or the right USB drive will then force you into the Recovery mode. But you can't install the stock OSX that came with the Mini, which was Mountain Lion (10.8), because it can not read nor write an existing APFS partition. APFS starts from High Sierra and up. Which is what you are seeing now; you're in a rock and a hard place.
There's a lot of incorrect items in this post.
Actually I'm speaking from experience as I had the same issue as the OP with my Macbook Air 2014, which came from Apple Canada where they helped me restore it. Actually, you can delete the partition in a regular recovery if you have access to diskutil and the terminal from the installer. In terminal, you can execute this command first diskutil list to find the boot drive identifier and then diskutil apfs deleteContainer /dev/drive identifier from diskutil list (disk0s2 for example). Once the container is deleted, you can then install the OS and the installer will then format the drive to whichever format it is best for and update firmware for the mini if need be. That was how Apple did it for me through recovery.
Yes, you can delete partitions from the standard recovery partition, but you cannot erase the entire disk. This will likely cause problems when trying to go from APFS back to HFS+ and may indeed leave the disk in a non-bootable state. Starting from either internet recovery or a USB boot disk will allow easy erasure of the entire disk without having to resort to command line tools which many users may not want to use or may not understand.
LOL, not yet. I only have a bluetooth apple keyboard and I cannot get it to pair in recovery mode. I will get a wired keyboard from work tomorrow and try it after I get home.
make sure you have a wired mouse in the room also, and good luck
So I did this and I am up and running. Thanks everybody. I will say that with 4GB of memory Catalina isn't super quick.
I think I’ll pull 2 8GB chips out of my iMac and put them in the mini just to see how it runs. All I want to do is sell this thing.
