Thanks for the reply, but my question is about external hard drive issue. As I mentioned in the post, what I am worrying is if it causes trouble with the hard drives.
When I used 2.5" portable hard drives, they were connected to the usb hub and it caused the issue. All of them got the logical bad sector and I had to throw them. I began to connect them to the main port of my computer and the issue had gone. I am using laptop now and have several 2.5"...