Hard drive not showing up after installing a different hard drive...

[MrFSXguyHD]

I recently dug out a old Seagate hard drive from a TV box that I had laying around. I just put it in and installed it (plugged in the cable but didn't turn it on. I turned on my computer and I received a error message saying it was unreadable, yet my bios settings are always set to read from my Mac OSX SSD as a first priority. So, I unplugged the hard drive and restarted my computer. And it just booted into my Windows SSD. I checked Disk Part, and it only recognizes my Windows SSD, but not the Mac OSX SSD.

I don't know if it the Seagate hard drive has corrupted my SSD or what. What has happened and how do I fix it?
Thank you

 

[MrFSXguyHD]

I recently dug out a old Seagate hard drive from a TV box that I had laying around. I just put it in and installed it (plugged in the cable but didn't turn it on. I turned on my computer and I received a error message saying it was unreadable, yet my bios settings are always set to read from my Mac OSX SSD as a first priority. So, I unplugged the hard drive and restarted my computer. And it just booted into my Windows SSD. I checked Disk Part, and it only recognizes my Windows SSD, but not the Mac OSX SSD.

I don't know if it the Seagate hard drive has corrupted my SSD or what. What has happened and how do I fix it?
Thank you

I checked the BIOS boot options and they had been changed completely

 

[kiiroaka]

Sounds like the UEFI got confused.

I would power the the PC, pull the AC cord, disconnect all disk drives, re-connect the AC cord, get into the BIOS and do a set to Default values, re-boot, get back into the BIOS, change the default settings to the ones needed by OSX (selecting UEFI or Legacy (CSM), turning off VT, turning off serial port, etc.), save the settings, hit the power on button when it starts to boot back up, pull the AC cord, connect the disk drives, re-connect the AC cord, power up, get into the BIOS, set my boot priority, reboot and hope that everything works like it should.

Before installing any new drive into the PC it helps if you first format it to a format that an OS can understand, like NTFS, FAT32, etc. Chances are that the old TV HD was formatted in Legacy mode and when you installed it into your PC, that is set up for UEFI, it confused it. An external caddy is a good investment, imo, since it can be turned on after the OS is up and since it connects through an USB port it will be isolated from the OS installing drivers.