When trying to update from 8u45 - b13 to the the latest available on java.com i.e. 8u45 - b15 received an error message as below.
ERROR
"A newer build of this version of Java already exists on your system. It is not possible to install
an older build. Click OK to exit this installation."

Also see attached screenshots.

Steps to reproduce:
1. Installed Java version on my Windows 7 system is 8u45 - b13.
    java -version output:
   C:\Users\khs>java -version
   java version "1.8.0_45"
   Java(TM) SE Runtime Environment (build 1.8.0_45-b13)
    Java HotSpot(TM) Client VM (build 25.45-b02, mixed mode, sharing)

2. Now download and install 8u45b15, latest version available of java.com
You should see this message.