We need to configure class path on windows in case they are not already configured.

Classpath is where jmeter will look for jar files.To set it go to my computer properties.Advanced System setting,Enviromental variables and then under system variables choose the varible path and click edit and dont delete anything go to the end and type ; and then paste C:\Program Files\Java\jre1.8.0_65\bin

We may sometimes require to add a user variable named JAVA_HOME.

For that we may go to System variables click add new and give name as JAVA_HOME and in the location give C:\Program Files\Java\jre1.8.0_65(not the bin in the end).