MultiBoot for OS X

Hello there,

How can I resurect my external drive in order to make it a dual boot (LION+SNOW)?

I tried many things but none was working like other external hard drive.

Now I can see the drive in the Disk Utility apps but not its first partition so when I initialise it, it return an error mesage on the formating process : unable to write on the last bloc. Whatever the format I chose : (Extended Journalized, PPC or MBR for MS-DOS).

then it dissepears from the apps. I have to power recycle it, and launch the process from the Virtual Disc and start all over.

Is there a way or have I screwed up the drive beyond repair?

Model : My Passport

P/N : wdbaaa3200asL-00

Thanks for any help.

Wassif

Format the drive HFS+J 

this will make it compatible with both Leopard and Lion