@lewiskwan_cf_jf
Welcome to the Autodesk User's Community..
The product key you are using belongs to ACAD LT 2018.. You are trying to activate AutoCAD 2018. Different product.
Also there's no need to create another document (like Word) and attach your image to that file. Just follow this procedure if you need to attach an image to your posting: https://forums.autodesk.com/t5/inventor-forum/embedding-an-image/td-p/7695110
One more thing.. Never any sensitive information here such as email address, serial #, subscription account number, business address, and phone/cell #. This is a world wide peer to peer network and such items should not be posted here for security reasons.
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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