Starting with ROBOTC 4.0, you can now manage your licenses remotely using the ROBOTC Customer Service portal: ROBOTC Customer Service portal.
Log in to the Customer Service portal using your license ID and password, then navigate to the 'Licenses and Activations' section.
Select the correct license from the list of available licenses tied to your customer account, then select the 'Manage Installations' option. This will bring up a listing of all computers that are currently activated with that license ID and password.
Click the red 'X' button next to each computer you wish to deactivate, this will deactivate the computer remotely and restore the activation back to your license.
This will allow you to reset (release) the activations from any computer that currently has ROBOTC 4.0 activated with your license.