Try the Methods provided below and check if the issue persists.
You may not have support for the exFAT file system. If you add support you may then be able to format the drive.Install this update to add support for the exFAT file system format for Windows XP
Note: Make sure you take the backup of important data before formatting the drive.
How to format USB drive with NTFS
a) First, connect your USB device to your computer. Then right-click on My Computer from the desktop and choose Manage.
b) Next click on Device Manager and then expand out Disk Drives. You should see your USB drive listed there as “Generic USB 2.0 USB Drive” or something similar.
c) Now right-click on the USB drive under Disk Drives and choose Properties. Then go to the Policies tab.
d) Now you will see two options, the “Optimize for quick removal” selected by default. Go ahead and change that by selecting the “Optimize for performance” option. This enables writing caching on the drive and therefore allows you to format it as NTFS! Sweet.
e) That’s it. Now click OK and then go to My Computer. Right click on the drive in My Computer and choose Format. In the File System drop down you will now see the option for NTFS!
Description of the exFAT file system driver update package