Cannot Transfer Large files from one ext HDD to another

[Jacquesmc12]

Hello
Im trying to transfer extremely large files from one external hard drive to another, a La Cie to a WD. By large i mean 100-300GB. It starts to transfer and then says a file containg that name already exists. here is how it is setup
La Cie(Content) --Firewire 800---->Macbook Pro---FireWire 400--> WD(empty)
im trying the drag and drop method.
Am i doing something wrong is there a free program that can do this for me?
Thanks

 

[angelwatt]

What file format are the drives? FAT can only handle up to 4GB files.

 

[Jacquesmc12]

Yes they are both FAT. The files are actually folders that contain hundreds of smaller files 500mb- 3Gb. Is there a way to do one big transfer?

 

[angelwatt]

Give Grsync a try.