@LH_6906818,
During the automated license requests for Mathcad Prime, the user machine will communicate with the PTC Server to request a license file. During this process, the user needs to login with their PTC account username and password. If the error "401: Unauthorized User" is received, that means that the user has input an incorrect username and password.
Hence, make sure correct credentials are entered.
Share snapshot of error if my above assumed error is not correct.
