Unable to read Lacie external drive

If cooling is an issue problems might prevail until you clean the dust from the vents and air-ducts inside your laptop. If you think you see filter pads in the air ducts they're probably piled up dust instead.
Also is your external drive OK and is the data transfer rate from the disk good enough for HD video material?
Try copying one test file onto the desktop for testing.

Thank you for asking your question with FixYa Support.

I am not sure what type of computer you have that your LaCie is connected to, but first and foremost, make sure the external hard drive has been properly formatted to work with the operating system your computer has.
For Windows computers: the LaCie should be formatted in either FAT32 or NTFS (recommended- more secure).
How to Format a HD in Windows Vista
For Mac computers: the LaCie should be formatted in Mac OS Extended (Journaled) format.
How to format an external hard drive in Mac OS X


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If your LaCie is already formatted, then the best way to import your entire iTunes library from the internal hard drive of your computer into the LaCie, especially if you are unable to drag and drop the library into you LaCie, is to try a simple copy and pasting of the ENTIRE iTunes folder from its home on your computer to the LaCie hard drive.

You can also use the website I like to reference which provides some good alternatives to effectively migrating your iTunes Library from a PC or Mac to your external hard drive:

Here is that support link:
How to Transfer iTunes Library to another Computer
(also included in this article, are external hard drives)

For sake of space, I want you to review this article, because I not only agree with its content, it is exactly what I would explain to you as well in a more condensed, easy to follow fashion.

I hope I have helped guide you well on your question.

Regards,

-Mactechtrainer

just open your external HDD case, look for the connector (SATA or IDE), so buy new external harddisk case according the connector type.

>> my computer could not repair the hard drive

It seems that the disk-drive is "dying", and the "table of contents" on the hard-drive has become corrupted, and automated attempts to "repair" the corruption have failed.

>> the hd is being offered with limited functionality, basically read-only.

Yes. Take this as a "hint" that the disk-drive is about to "die".

>> It recommends that I back-up the info elsewhere

Good advice. Take the advice.

>> and reformat.

This may help -- it will identify any "bad" spots on the hard-drive, and will either permanently avoid using those bad spots, or it will allocate a "spare" track on the drive to be used as a substitute for the "bad" area.

However, even after doing this, I would not "trust" the device to be a "reliable" backup for my important files. Like a well-used chalk-board in a classroom, the disk is getting "worn-out".

If it's still under warranty, exercise the warranty.
If the warranty has expired, replace it.

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... 

Don't know about the MAC part, but an I/O error implies that the either the source file cannot be read or the destination drive will not write. This is usually an indicator of a bad HDD. To check, I would attempt to connect the external drive to another computer. If it still gives the same indication, contact the drive manufacturer about data recovery recommendations

You can try to boot up with Linux LIVE cd and plug on the external HDD.

you may need to get a new driver for that lacie from their website..

support downloads, model o/s

If you open it up you will see that the drive is a regular computer drive. You should be able to plug it into a computer as a secondary drive and try to get the data off. But if it's clicking and making noises there may be no hope. Sorry!

How much are you attempting to copy at once?