Lacie d2 HD Quadra 250gb

I've had issues with the lacie mini power supply before. I can cause some wierd issues. Unfortunately, it isn't the cheapest thing to replace but that's probably the best place to look first.

click start control panel administration tools computer management device manager look through all of your devices if you see a yellow question mark?or exclamation mark ! or red x
right click to reinstall drivers or

if you can see your usb but its not working
ports(com&lpt)right click update driver

if this fails to fix the problem

check usb leads for secure dust free seating

sometimes the wires inside the cable will be damaged due to bending or stretching or placing heavy equipment upon the cable

just replace the cable of the hard disk, when you plugged the external disk drive you got that windows could recognize the USB device change the cable everything should work fine again,

check the USB leads that attach to the motherboard usually red-white-green-black make sure they are securely seated and have no dust build up on them dust will cause static and a lot of unforeseen problems
hope this helps

what os do you have

Check with LaCie's support site at http://www.lacie.com/us/support/ and it's a good idea that you write down the serial number of your external disk.

try to connect lacie to windows base computer if it work, there a problem, with your mac book check if device manager recognize lacie drive if not check for the fire wire port.

am not so sure if this is a similar issue with iomega external drive in which the drive wont show up on My Computer but when the external drive was plugged into an ubuntu machine the drive was being detected and working just fine.

Please try to do the same. plug your external drive to an ubuntu machine and lets see if it can be detected. If it is then the hard disk has a similar issue with iomega drives. check this link for the solution.

My 1TB Lacie suddenly won't power up (no sound, no blue light). It turned out that I might have worn out the on/off switch over the seldom-use 4 years of usage. I push and flip the switch multiple times, and the Lacie came back to live and mount normally. I will just leave it at the On setting and simply pull the power cord when i want to switch it off.

Obviously, Lacie failed to do QA on the on/off switch because my 4 years usage did not totalled to more than 10 on/off per month.

take the drive out and put it in a external case and see if that helps. if not the drive is dead.

Modern hard drive motors can easily become seized after an impact. The only DIY solution I am aware of is the use of a heat gun over the back of the drive motor. The build up of heat within the motor is sometimes enough to free it.

If the drive was running the problem may be due to a phenomenon known as "sticktion" where the drive head is actually stuck to the disc surface. If this is true then you need a data recovery company.

Contact Lacie support for a new power supply. I had the same problem, contacted Lacie support, they sent me a new power supply with power cord and all is well now.