WARNING: FOLLOWING THESE STEPS WILL ERASE ALL DATA ON YOUR DRIVE. PLEASE BACKUP ANY DATA BEFORE PROCEEDING.
All G-Technology drives are formatted for Mac Operating System. To use these drives on both Windows and Mac platforms, you have two options.
A) Format your drive ex-FAT (preferred for Windows Vista/7/8)
For instructions on how to format your your G-Technology drive using the ex-FAT format, please visit the following link:
B) Format your drive FAT32 (for Windows XP and older)
On a Mac OSX machine go to 'Disk Utility' and your drive should appear on the left. Click on the drive and at the top of the current window, the ERASE button should be available. Click on Erase and under 'Volume Format' select 'MS-DOS File System' (FAT32). With this format, you will be able to READ/WRITE on both windows (2000/XP) and Mac OS machines. (NOTE: You could format your drive on a Windows machine FAT32, however Windows limits FAT32 partitions to 32GB)
There is an issue with 'MS-DOS File System'. It cannot write files over 4 GB. If you are working with files over 4 GB, you will need to choose option C.
C) Purchase a program like MACDRIVE
MACDRIVE is installed on a Windows based computer and will allow you to read and write to a Mac formatted drive. You can learn more about MACDRIVE click here