I have here an external HDD (closed cage). Now the drive or the controller seems to have a problem. If I connect the drive via eSata the hard disk indicator (LED) is lighting up all the time. Normally it will blink when something is read/created/deleted. I can access the files in Windows 7 explorer but there is a huge lag, e.g. if I change into a subfolder it takes about 5 minutes. I tested this also on another PC - so the hard drive has a problem. I also tried the tool for finding errors (right click on hard drive, properties, tool for finding errors), but that didn't changed anything.
What could be wrong with the HDD? Does it help if I crack the case and connect it directly with my PC?