Brava Reader has an annual built in "expiration". After you download the installer, it is free but, it will expire and "die" after one year. So you need to remove and install a newer copy. The trick to removing it it putting a -y at the end of the command line to avoid the "are you sure" message.

In reference to both of the prior posts that indicate how to do a silent uninstall, neither results in a "silent" uninstall. The -y switch allows you to uninstall in an "unattended" mode, not a "silent" mode. There is a difference. The message boxes still show up on the monitor albeit for a brief moment (just enough to freak out end users, usually resulting in a call to their Help Desk).