Why must the two large ends of the Y-cable be plugged to an USB2.0 host? Any affection if I plug only one?
It needs more than 600mA to spin up a HDD, but the USB 2.0 can only provide 500mA for maximum. Insufficient power supply of the HDD often shows "ask for format" message or can`t be recognized on your computer. The long period of the insufficient power supply could make the motor of the HDD malfunctioned and even cause data loss on your StoreJet.
If your computer does not have extra USB port, we recommend that you purchase a Transcend USB Power Adapter (TS-PA2A http://ec.transcendusa.com/product/ItemDetail.asp?ItemID=TS-PA2A) to provide sufficient power. Step1, plug the main line of the Y-cable(the thicker line) into the USB port of your computer. Step2, plug the spare line(the thinner) into Transcend USB Power Adapter, which will give the StoreJet sufficient power. Step3, plug the other end (the small end) of the Y-cable into the StoreJet.
You also can use the USB hub which is powered by adapter. Just like the picture which is shown below.
You can select each one of these 3 steps we described before, then your StoreJet will operate successfully.
Note: If you use a notebook, please make sure you have plugged the AC adapter.