Launch the software using the (do not use the original VCDS shortcut). Go to Options within the VCDS menu and click Test .
The official software is distributed free of charge by Ross-Tech for use with their genuine hardware interfaces (HEX-V2, HEX-NET). Licensed users can download version 21.3 directly from the official website and use it without restrictions.
VCDS 21.3 is a version of the VAG-COM Diagnostic System used for diagnostics and coding on Volkswagen, Audi, Seat, and Skoda vehicles. While the latest stable version has moved past this release (e.g., version 23.3), version 21.3 remains common for specific hardware setups. Download and Installation Overview The VCDS software is designed to work exclusively with dongle-based interfaces. Software Source
: Includes over 20,800 fault codes and control module descriptions.
Enhanced descriptions for control modules and fault codes, making troubleshooting more precise.
The loader has likely modified your hosts file ( C:\Windows\System32\drivers\etc\hosts ) to redirect ross-tech.com to 127.0.0.1 . This blocks the software from checking for updates or invalid licenses. It also may have installed a background service that sends your PC’s information to a command-and-control server.
In the diagnostic community, a "loader" is a third-party tool designed to make the official VCDS software work with unauthorized or "clone" hardware interfaces. It typically bypasses the firmware checks that the official software performs on the connected cable.
In legitimate software, you simply install VCDS, connect your genuine Ross-Tech cable, and the software runs. No "loader" is required.