Could not find valid Java virtual machine to load.

I'm trying to install the Runtime Components for Identity Management 7.2, and get the "LaunchAnywhere Error - Could not find a valid Java virtual machine to load. You may need to reinstall a supported Java virtual machine."

I've installed NW7.3 EhP1 JAVA (only) on a MS Windows Server 2008 R2 Enterprise with SQL Server 2008 R2.

So by following those top notch Installation guides , got the Designtime components installed, but continue to get the above error after clicking on the "Install" file for the Runtime component, that was included in the NW Identity Management download 51039798. I've even downloaded the most recent SPĀ  "ICRUNTIME06_1-20005938" and tried with the install file in that package, with the sameĀ  result.

I've downloaded and changed the JVM to JVM 6 and JVM 5 (JVM 4 was installed as the default with NetWeaver 7.3). Although I am unclear on which variables needed to be added in the Environmental Variables, but have added the JAVA home, path and CLASSPATH.

Can anyone let me know what's the correct procedure to "reinstall a supported Java virtual machine" this is asking for? Or if there is something else I should be doing to correct this.

Muchly appreciated

Ken H