@Anonymous
Are you 100% sure the serial # matches the Revit version you requested and downloaded/installed? Most time this message appears because user request a given version but installed a different version.
Go into your Autodesk Account and confirm.
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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