If you have lost your credentials or are having trouble with a legitimate license, the best course of action is to contact Autodesk Support for a manual activation override. Are you having trouble locating your serial number

To activate Autodesk AutoCAD Civil 3D 2018 , you typically need a combination of a Serial Number Product Key

: Ensure you are connected to the internet. The software will communicate with Autodesk servers to verify the credentials and authorize the workstation. 3. Activating Without an Internet Connection If the workstation is offline, the process generates a Request Code

Sign in, enter your Request Code, and the system will generate an Activation Code (a long string of characters).