In order to overcome the 4gB limit, you'll have to format the external drive with the NTFS file system.
Open an instance of cmd.exe (Go to Start and type in cmd.exe - at the top of that window will be the file, right click on it and select "Run as administrator")
Use the following syntax to convert the drive to NTFS (I got this by typing "convert /?" at the cmd prompt).
Quote
C:\Users\FUBAR>convert /?
Converts a FAT volume to NTFS.
CONVERT volume /FS:NTFS [/V] [/CvtArea:filename] [/NoSecurity] [/X]
volume-----------------Specifies the drive letter (followed by a colon), mount point, or volume name.
/FS:NTFS---------------Specifies that the volume will be converted to NTFS.
/V-----------------------Specifies that Convert will be run in verbose mode.
/CvtArea:filename----Specifies a contiguous file in the root directory that will be the place holder for NTFS system files.
/NoSecurity------------Specifies that the security settings on the converted files and directories allow access by all users.
/X-----------------------Forces the volume to dismount first if necessary. All open handles to the volume will not be valid.