Ross-Tech charges any buyer of a pre-owned/used cable a $99 USD registration fee to gain access to SW updates and support. Check their website for the details.
Quoted direct from the Ross-Tech website -
This interface acts as a "dongle" for VAG-COM, so the software should be fully functional on any PC you use with the HEX-USB+CAN. However, product support is provided only to the original purchaser. If you buy a second-hand HEX-USB+CAN from someone and want support, you'll still need to pay $99 to register.
I've always wondered why folks reselling R-T cables don't factor that $99 USD registration fee into their asking price?
Comparatively, a new, properly licensed HEX-USB+CAN cable can be purchased direct from R-T for $349 USD.