Has anyone else experienced this? We're trying to get a network license working on our server here and cannot get our copy of ACAD LT 2013 to work with register once.
Did you purchase the license in the US or a different country by chance? If so that would explain the error.
I'd be more happy to look into this for you if you could send me a Private Message (click on my philip.s profile name and then "Send this user a private message") with your serial number + any relevant order info.