External HDD File Transfer Freezes

Hi. When I'm copying files (350MB+) to my Samsung STORY 1.5TB External HDD after one files is copied the file transfer freezes. After a few seconds I get a message saying the files cannot be located in H:/VIDEO and suddenly it says my external HDD is empty. I can't access the HDD (which has over 300GBs on it already) again until I reboot. I have installed this hotfix: You encounter problems when you move data over USB from a Windows 7 or Windows Server 2008 R2-based computer that has an NVIDIA USB EHCI chipset and at least 4GB of RAM. It doesn't work however relevant it is to my problem. Any suggestions would be greatly appreciated.

*Also my iPod will have trouble being detected in iTunes. After reboot it works fine.
**Just noticed the "External USB Hard Drive Problems" thread. Unfortunately only the hotfix seems to be suggested.

Hm...sounds like either one of two things...

1. Faulty chipset driver...reinstall your chipset drivers
2. You are having faulty power issues on the USB which would in turn mean hardware failure