To understand the error, we must deconstruct the components of the message:

If you are using a VPN, disconnect it, as activation servers often flag these as suspicious or blocked regions. 2. Re-enter the Activation Code Carefully Manual typing often leads to errors.

If you are running a version from 2020 or newer, download the latest Autodesk Licensing Service update from the Autodesk Support Site

If you have recently formatted your computer or moved the software to a new machine, the server might think you are trying to install the software on too many devices. In this case, only a support representative can "reset" your seats to allow a fresh activation.

The error often manifests when local network settings block the specific ports used for the "handshake."