Java runtime system not found after installation or reinstallation   spacer
  Whenever you have deinstalled the java runtime environment (JRE) from Windows and you reinstall it later in a different directory you may stumble on the unexpected message:

The Java Runtime Environment cannot be loaded from <.....\bin\hotspot\jvm.dll>

at an attempt to run some java code from within a browser.
How it was solved   spacer
  Open the Java Plug-in from the control panel. If it opens then the JRE is live and running. Click on the advanced tab and select from the roll down list the environment to be used by your programs. Close the panel and reload the page or code requiring Java.
Often after installation this option is left to "Use Java Plug-in Default" which may translate in a pointer to a JRE no longer present and causing this way the above mentioned message.