@diemobarz
This is not Autodesk. This is mainly a peer to peer network where user's are assisting other user's like your self. However since we have no insight into your Autodesk Account, I'm assuming by the information you provided it sounds like you have a CLIC license. This is a cloud based license and there's no serial #/product key required. However you said its showing serial #/product key filled in already from existing seat. What version is this from the existing seat? If its 2017/2018 perform a license reset per these steps.
Please note, folders of C:\Programdata and C:\Users\[Username]\Appdata (listed below) are hidden folders and you may need to adjust your viewing settings.
First make sure you're signed out of the desktop app and A360 (both are located in your Windows system tray
On your computer, navigate to
2017 Version: C:\ProgramData\Autodesk\CLM\LGS\<Product_Key>_2017.0.0.F [<Product Key> is the product key of the application you have]
2018 Version: C:\ProgramData\Autodesk\CLM\LGS\<Product_Key>_2018.0.0.F [<Product Key> is the product key of the application you have]
Delete the LGS.data file.
Navigate to C:\Users\[username]\AppData\Roaming\Autodesk\ folder
Delete the ADUT folder and it's contents
When you start the application, it will prompt you to choose one (that matches your license) of the following:
Login - 30 day trial or CLIC (Cloud Based) licenses
Serial Number - Students, Standalone and Single-User Term Based activation
Network - Network License server for obtaining licenses from a machine on your network
One final thing.. Its the weekend and if there's something wrong with your account, you will have to wait until Monday. If you need to work today you can put your application in a 30 day trial until its resolved. If the above information doesn't work (besides the trial mode), you can contact an Autodesk Agent here on Monday. Just remember for the future this forum is not an official way to contact Autodesk for support. To get support you have to create a case through your Autodesk account or contact the correct department using this information.
Good luck and report back on your progress
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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