Josh;
Windows XP Home or Pro?
Home does not have that capability.
For Pro, you need to be using NTFS file system and not FAT32.
To check:
Open My Computer, Right click the drive, click Properties.
What does it say by "File System"?
To convert to NTFS: http://aumha.org/win5/a/ntfscvt.htm
Data should be safe, back-up important data just in case.
