Good day to you all, Happy Easter! I have upgraded my MacBook Pro to a 250 GB hard disk. One of the purposes for this was to make a Windows partition. This is and was my schedule: 1. I made a backup of my MacBook Pro to an external hard disk, time +3 hours! I used CCC Carbon copy Cloner. 2. I mounted the Leopard Install Disk, the message was I could not install Leopard on my Macbook Pro. 3. I connected the MacBook Pro as an external harddisk to my desktop and installed Leopard on the MacBook Pro. As the desktop is a PowerPC one, Bootcamp Installer was not installed in to Tools, but I had save it, so I could copy it back. 4. I booted the MacBook Pro, and started BootCamp Installer. The manual was fine, but continuing there is a message I can't install Bootcamp on the hardisk. It has to be reformatted in the GUID mode, AND WHAT IS THAT? 5. The above written is just a short cut of my work to find a way to get Windows on my upgraded hard disk, I have to give up now. 6. So, what's wrong? Leopard is updated, the only "change" is I do have a 250 GB hard disk instead of the original 100GB. 7. My MacBook Pro is of he first generation. 8. Boot camp fails to allow installing. 9. GRRRRRR Anyone knows the trick? Whats' GUID formatting, I can't find that option in the Disk Manager. As I started, folks, do have a Happy Easter! /Hans.