Have you recenlty updated either Bridge and/or Photoshop and/or ACR?
Try starting up Photoshop and be sure that it's running before trying to open a raw image. Also, go into Preferences and see which is checked: run ACR in Bridge or in PS. Whatever it is, try the other option.
Thank you.. I haven't updated any apps on my MacBook Pro recently. eventually after several re-starts the issue resolved itself. So I'm still unsure why it happened but happy o can open my jpgs into raw editing again. cheers