Hello guys!
I have been trying to install Houdini apprentice edition 15.5, but every time when I click on activate my apprentice license it'll show me same license window again and again i don't know what to do. Because of this problem i'm not able to use software. if anyone know anything please let me kmow.

Uninstall what you have.
Then re-install, download Houdini 16, not the old 15.5.
When the installer asks to Choose Components, choose Apprentice Licensing, not the default Commercial Licensing.

You don't really need to activate the Apprentice license, just launch Houdini after the install and it will license itself.

A related query: The license file contains a date which is approximately after 1 month. Evenif we delete that file and recreate automatically for the same machine by opening apprentice, the date in the file is set to that same old date. Does it mean that we can't use houdini apprentice after 1 month of license validation?

Thanks
Jojan