The activation Key came up not valid. The license said good until 2016. What now? I still can't open my e-mails.

Hello Clarence, not quite sure what you’re referring, if you have your activation key, all you need to do is to activate the application in Help > License > Activate and confirm the activation by pressing OK. If you have any issues with the application setup, try to check out our FAQ page in order to get you started with eM Client at http://www.emclient.com/faq

Regards,