@Anonymous
Welcome to the Autodesk User's Community..
Windows 11? Do you mean WIndows 10?
AutoCAD 2012 will not function properly and is not supported under Windows 10. You may not want to go down this route because an update to Windows 10 can take this legacy version down and make it inoperable.
Anyhow you need to provide more details in why you can't activate it. In addition activation is only possible if the serial # you have is still activate at Autodesk end.
There are numerous activation issues and we the users have no idea what you're faced with. Before posting any message make sure to blur out any sensitive info.
Mark Lancaster
& Autodesk Services MarketPlace Provider
Autodesk Inventor Certified Professional & not an Autodesk Employee
Likes is much appreciated if the information I have shared is helpful to you and/or others
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