So, im in a bit of a weird situation. I have an iMac 2005 which was running ubuntu. So i wanted to change to POP!_os. I took the harddrive out, plugged in to my windows pc etc. the point is that the hard drive is fully functional with pop_os on my windows pc. However when i put it back in my iMac, it starts with a grey screen and displays a grey file with a question mark. After a few tries to get it to work( trying different software, different drive) without any success, it even stopped displaying tha file thingy. Is there anything i can do besides throwing it away?