If this is a secondary drive, you can do this from within Windows (Start Menu, Programs, Accessories, MSDOS Prompt). If this is a primary (C) drive, you must do this from DOS mode.

1. Type FDISK and hit Enter. Y and Enter to the 'Enable large disk support.'

2. Hit option 5 (Change current fixed disk) and select the appropriate drive, hit Enter.

3. Select option 4 to verify you chose the correct drive.

4. If your drive is already formatted for PC, you will need to erase the contents of this drive. If this is a new or Mac formatted drive, skip to the next step. Hit Option 3 (Delete) and then 1 (Primary). Select the partition number (usually 1) and Confirm the Volume Label by typing it in exactly as it appears on the screen, then Y and Enter to confirm.

5. To create a partition, do Option 1 (create) and Option 1 (Primary). Yes to 'use all available' and then give it a name (11 characters, no spaces or symbols). It will check the disk twice within this process.

6. It will confirm that you've created the partition, and that you need to reboot. Hit ESC a couple of times to get out of Fdisk, type EXIT to return to Windows, and restart the computer.

7. Upon reboot, you will have a drive letter in the My Computer assigned, but if you double-click it, it will be unreadable. Do this to confirm the drive letter before formatting it.

8. Then right-click on the drive letter, go to Format, and select Full. Hit Start and OK to the box that pops up. The drive is now ready for use, no restart is necessary.