Connecting USB HDD problem I have 3 HDD connecting to my computer via USB, the first two HDD work fine, however when connected the third one, "!" sign appeared at the device manager, I swapped those HDD to test thus not related to HDD problem, thus, the first two connection have no problem but third device cant be connected, what problems do you think? Thanks

I had a similar problem & found that if I powered the HDD's from an external source rather than the USB card it all worked. You don't say what type of HDD's you are talking about but in my case they were 60GB 2.5" laptop drives and they take a fair whack of power. I think you may have reached the power limit of your USB card. Rgds. Bob Mitchell.

Are these all unpowered enclosures? I assume all the USB ports being used are active working ports? Are all the USB ports being tried USB 2? Are you using a USB hub, or directly to the computer?

You don't say where you're connecting these, but I've had a number of experiences with desktops where using a front or front/side connector is useless, and the PC hangs, but rear connector's fine. (Whether or not both connectors from the drive are plugged in- and that's just a single drive). Good luck!