I installed teamviewer 12 free on a cloud server on Amazon AWS, when I launch TW I receive following error "Trial version expired (Administrator - Amazon).
How can I solve?
try to see this Knowledge Base. But also please note this:
Personal usage of TeamViewer is not possible on a Windows Server operating system! This automatically qualifies as commercial use and requires a license.
If your goal is to connect to the server for maintenance (from another client device) then you can install a Host module on the server.