From
https://sites.google.com/a/interpss.org/interpss/Home/user-gude/user-guideinstallation-guide"You may need to modify install.bat, if your
Java installation is not in your Path."
If you are using Windows just go to Control Panel, System, Change Settings, Advanced, Environment Variables.
In the user variables create a "New..." variable called PATH and set its variable value as the address to where your Java is installed. For me that is C:\Program Files (x86)\Java\jre7\bin.
You may need to restart your computer after clicking OK etc.
After that just retry installing.