Instructions
Find and purchase a Game Boy Advance flash linker cable. Power on your computer and wait for the operating system to finish loading. Insert the software disc that came with the linker cable into your computer's CD or DVD drive. Click on the option to run the disc's program when a window pops up asking what action you want to take.
Follow the instructions to install the driver. Insert the flash card into the card slot on the Game Boy Advance console. Plug one end of the linker cable into the Game Boy Advance.
Plug the USB end of the linker cable into any open USB port on your computer. Close the window that will pop up asking what you want to do with the attached device. Double click on the "My Computer" icon on your computer's desktop.
Locate the entry for the Game Boy Advance linker cable in the list of drives attached to your computer. Choose the "Format" option from the menu that will pop up next to the drive name. Click on the "Continue" button when your operating system brings up a new window asking if you are sure you want to continue.
Click on the "File System" button, then choose the "NTFS" option from the drop-down menu. Click on the "Start" button at the lower left side of the window to begin the formatting process.