I have AC 16 and this version is enaugh for my job. So, when I try enter to AC I received 503 Error. AC is not detected License Key and showed me register site. GS Dealer is hard to talk and is not to give me email and password to enter the AC? How can I start AC with a registration key without login credentials for sites I never had?
This is pretty strange. If license manager can read the info on the USB key, then the issue isn't a problem with the USB port itself (with "try another port" or "reboot" being the solution).
So... since it is Archicad that doesn't see the keyplug, I wonder if perhaps you don't just need to update or reinstall your Codemeter or WIBUkey software? Being Archicad 16, I suppose you might have a WIBU key (plastic)? If it is shiny metal, it is Codemeter. See what version of runtime you have vs what is available here: