<RoboHelp HTML 9 - CHM file> how to insert a system time variable to project.

Dear all,

I used to work with Help&Manual, I usually insert a variable into the fist page of online help. This variable automatically takes the current system time each time I generate the project to CHM file. Therefore, we can know the online help is new or old.

Can I create a variable like that in RoboHelp ?

Thank you.