Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Doesn't work for me

I bought four of these, all at the same time and all from the same vendor. Perhaps it's a lot problem, but they are all junk. They are constantly dropping connection and I have to unplug the hub and plug it back in to get the devices that are plugged into it to be recognized again. I've used these hubs on XP, XP 64-bit, and Vista and they drop connections on all. These are all different brands of computers and in two different physical locations so I know it's not my computer. Cables To Go 7 Port USB 2.0 Hub that I replaced them with has had no problems with dropping connections.