I am not familiar with hardware but managed to open my Seagate 3T external hard drive and bought a SATA connector as advised. I thought if I just plugged it in, I'd be able to get the information, but it says I must format and will lose all my data. That's exactly the reason I got the SATA connector in the first place, so that I could get the data from the HD.
I am having the same issue as what is mentioned above with exactly the same error messages and do not want to lose all the data on my HD by formatting it. Can you please help?