Reading a Sony Memory Stick - "Upgraded" x50v WM 5.0

I have a 5 in 1 CF reader that I use to transfer pictures from my Sony camera to my x50v. I upgraded to WM 5.0 and now it won't recognize memory sticks in the reader. It will recognize SD cards. Has anyone else had this problem and developed a solution?

The error is as follows:

Unrecognized Card

Enter the name of the device driver for this card. For information, see the card manufacturer's documentation.

Unknown card in Socket 1