In the past updating Brava Reader has been a lengthy process often needed to be scheduled out, luckily IGC (the makers of Brava Reader) have simplified this recently so it is easy to do.
Begin by searching brava reader on google.com
Click on the first link bravaviewer.com
Then select the download of the free version
This will prompt a download to begin, after it has finished the installer will begin. Run through the windows and agree to the terms. After you click finish you should be able to view your scanned images again.