- Uninstall Java from Control Panel -> Programs -> Uninstall
- Need to remove three files from /Windows/System32 and C:\ProgramData\Oracle\Java\javapath (you need to view hidden files to see Program Data)
- This files are "java", "javaw" and "javaws"
- After you do this you should reboot and then install the java version you want (in this example java 1.7)
- After this you may want to go to the command prompt (Start -> CMD) and type java -version to see the installed version
Some additional steps that may be required.
- Go to Start -> Advanced System Settings -> Environment Variables
- Check that your JAVA_HOME is setup correctly