Windows 7: System crashed, lost administrative privileges to exfat drive

I'm running Windows 7 RTM, computer just crashed an hour ago and have noticed that I've lost write access to my D drive formatted in exFat, what gives??

Seems like the entire partition has been reset with a readonly flag.

Seen a couple of solutions on the net.

Try running a new command window in elevated mode, change to drive and run "chkdsk /f".

Or try using diskpart > select disk xx > select vol xx > att vol clear readonly

The diskpart didn't work for me, but chkdsk worked!! Sigh... haven't had to do chkdsk since windows98.