Hi all, I've got a 27" iMac, late 2012 model. Just around a week ago, I noticed that my external HDD which I hook up to my iMac using Thunderbolt just suddenly unmounted by itself. Initially, I thought it was my external HDD that was fried, but I decided to connect it using USB and it works fine. So, thinking that maybe it was a damaged Thunderbolt cable, I bought one and swapped it over to no avail as well. Perhaps it's the Thunderbolt ports then. I've tried just about everything from resetting the PRAM and NVRAM to even a fresh installation of the entire OS. On the System Information, on the Thunderbolt tab, it says "no hardware found". Is it really a hardware issue? Because where I live, there is no Apple Store, heck there isn't even one in the whole country. The next best reseller is 2 hours away by flight, and I can't possibly carry a 27" iMac on board. Any help would be much, much appreciated. Thanks all!