Yep !

I know - my XP has that update KB955704, but that does not do it - problem might be... 2 partitions, first is Fat32, and second is exFAT.

In Windows administration i can see the exFAT, but when i try to assign it a Drive-letter i get an error-message saying:
"The operation was not completed because the partition or device is not activated. Restart the computer to activate the partition or device."

I have been trying to restart - no luck

What i think i am looking for is a software tool for handeling the exFAT volume.