I started a dual-boot install at the end of the day, and now I’m in trouble and too tired to think right. After a basic default install,it only boots to mint now. No dual boot. I’m going to sleep now, but any pointers you can offer will give me a jump on my day tomorrow. Thanks.
You could try I think a grub probe command to get grub to rescan for other operating systems.
Setting up a dual boot while tired can be a bit risky, since it’s possible to slip up and install onto the wrong partition or drive and overwrite the other OS. Hopefully not the case here!
If your other OS is on a separate drive, you could also check your BIOS to make sure the SATA or PCIe slot its connected to is enabled.