Activating older software can sometimes result in errors due to compatibility or retired support services.
: If available, click License Details to see your assigned serial numbers and product keys. The Activation Process autocad+2009+serial+number+and+activation+code
If you genuinely own AutoCAD 2009 with a legitimate serial number but lost your activation code, contact Autodesk Support directly. They can help recover activation for valid licenses. Activating older software can sometimes result in errors