I was copying an avi file from the 250GB lacie porsche hard drive (USB2) and the USB cable got removed while the copy was in progress. I tried restarting the computer but the hard drive isnt regonised. it makes a strange noise when turned on, a different noise from before the problem began. also the power light on the hard drive now blinks orange and yellow (whereas before it was always orange).

The disk-drive has malfunctioned.

Search online for a professional "data recovery service".
For a significant fee, they can repair your disk-drive,
just long-enough to copy your files to a new disk-drive.

If it still has a valid WARRANTY, exercise the warranty to get it repaired/replaced.

If the warranty has expired, then open the case, remove the disk-drive, buy a new "compatible" disk-drive, connect it, and thus "revive" your external storage device.

Sounds like the hard drive in the Lacie has fauled.
To test the hard drive, remove it and connect it to an USB hard drive adapter and connect it to a working computer's USB port. If it deosn't detect it as an external drive and you connot open folders and files then it is faulty.
You can install a new hard drive in the Lacie and then format in FAT32.

Your copy process was interrupted so you'll need to perform the entire operation again to ensure you have all of your data and to also make sure none of it is corrupted.

I think the migration assistant (in the utilities file in your application folder) can transfer files direct via USB.

Are you trying to create one giant zip file or something similar? It sounds as if your Lacie 250gb hard drive has been formatted with a FAT32 filesystem and you are running into the maximum file size limit of 4gb minus 1 byte. Try just copying your files without using any compression utility or try reformatting your Lacie 250gb hard drive with the NTFS filesystem instead.

Unfortunately, when you copy a file, you are technically creating a new file hence it would assign the current day's date as the new date.

How much are you attempting to copy at once?

Do a bit of arithmetic - go to each folder right click, then click on properties and take note of the size of each folder. What does that add up to? Any unusually large files? Has it been partitioned at all?

You might try going to the manufacturers website and request a new one from them.

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