On a lacie external usb2.0 firewire 400/800 1TB, I'm getting a blinking blue led whenever the drive gets connected via usb. I dont have a firewire cable to test, but the drive was working fine on same cpu only a couple of day ago before we relocated it. I remember there was a specific boot process for this external drive, can you point me to it? Thank you!

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.

If the device doesn't show up in Mac System Profiler at all or as an unknown device:
The symptoms indicate there is a problem with the drive, how it is connected, or with the computer used for troubleshooting. The next best step is to change physical variables, and find a simpler problem than a broken product.

• Change the data cable (USB, FireWire, Ethernet, etc.) A failure in the cable can cause this issue.
• Change the external power supply or cable. If possible, obtain another power cabling to see if the problem is in that component. On drives that are powered via USB or Firewire, try using the included power sharing cable and connect it to another port.
• Change the computer you are using. Computer problems can manifest themselves in many ways. Even if the computer appears to be working properly, this is a worthwhile test. Try it on a friend's computer and see if it works fine.

If the tests above don't help, it's possible that the drive was either dropped while running, had a hard drive 'head crash' or the circuitry inside the drive is fried.
Hope this helps!

An external storage-device has four major components:

* the USB cable

* the power-adapter

* the disk-drive inside the enclosure

* the USB-to-disk-drive adapter inside the enclosure.

One of these components has failed.

Try a different USB cable.

Try connecting to a different USB port on your computer.

Try connecting to a USB port on a different computer.

Take a "multi-meter" and measure both the voltage and amperage output from the AC adapter, and compare with the specifications on the label on the adapter.

Open the enclosure, and remove the disk-drive, and then connect it as a "slave" disk-drive in a desktop computer, to see if it works at all.

Purchase a new, compatible, disk-drive, and install it in the enclosure, to "revive" your external storage device.

Get the part-number and serial-number from the label on your disk-drive, and access the manufacturer's web-site, and use "check warranty status", to see if they will replace the device, at minimal cost to you.

There exist commercial "data recovery" services that can try to repair your device, just long-enough to rescue and copy your files. For example, see: https://services.seagate.com/index.aspx?lng=en-US for a "no data - no charge" guarantee.

LED Indicators - LaCie 2big Network
The LED indicators above the drive bays and the front LED indicate drive status and activity.
During Startup

• Front LED – blinks red/blue until both disks are powered on, then turns solid blue.
• Rear LEDs – blinks red/blue until corresponding disk is powered on, then turns solid blue.

NOTE: If the device is not able to initiate the boot process following disk startup, the front is solid red.
During Bootup

• Front LED – solid blue
• Rear LEDs – solid blue

NOTE: If a disk is failing, both the disk’s corresponding rear LED and the front LED will be solid red.
During RAID Synchronization

• Front LED – solid red
• Rear LEDs – The LED corresponding to the original disk will be blinking blue and the one being synchronized is blinking red
• Once both disks are synchronized, their corresponding rear LED and the front LED will be solid blue.

have you checked the output on the power adapter when you plugged in? if not, there is no hard reset for the drive. you just have to isolate the board on you external hdd.

solved: after referring to the userguide, I found that I formated my drive with a OS format, which can not be recognized by VISTA >> formated to FAT32 and now it works... 

I ran into this issue this week with my lacie big disk 500G external. Unit would power on when plugged into a pc blue light would flash and nothing no connection ding from windows.
Blue front light would flash repetedly slight ticking sound from drives but no connection i finally fixed this and gained access to my data by opening up the case and pluging my pc 12v connectors into both drives to power them up but leaving them connected to the lacie internals worked instantly and ive since copyed all my data off my 500 and will just transplant the drives to internal use on my pc. you cannot connect the drives internally and then copy the data due to the fact that they are raid 0 stripped drives so this hybrid setup works if your external case isnt powering up the drive correctly as mine wasnt.

I support the comments of (fire sine) I have the d2 120gb Lacie and it was down for two years.  I took it to my apple guys and they said that I needed to go to a data recovery service which would cost a gang of money.  Come to find out, when I decided to update my internal hard drive on my Mac Pro, I had to buy a SATA, IDE, USB 2.0 adapter to back up the internal and transfer to the new internal. Long story short, something said, Hey try and open the Lacie and bypass the board in the enclosure and connect directly to the Western Digital drive inside.  AND WHALA! I got my info, so all I need is a new enclosure.  

Windows XP and most pcs running it does not natively support firewire,as it was developed by Apple computers. Most Firewire ports on PCs are 4 pin. Your PCI card ( and I take it, its a desktop youre referring to ) should have a 6 pin connection. Firewire connections also have a 7 watt supply via the bus. You may need to open the computer and see if the molex jack on the card is being powered by your computers power supply. Two firewire drives, especially the power hungry Lacie quadras, may be to much consumption for the card. Hope this helps.