I am having the exact same problems as Hermann. Adobe Reader DC Version 2018.011.20035 deployed through GPO, same settings as Hermann on the 'Online Services and Features' section of the Customization Wizard. Any advice?
I had read somewhere that if you don't accept the EULA that updates are not enabled. Could the 'Suppress display of End User License Agreement (EULA)' option being checked under the 'Personalization Options' section of the Acrobat Customization Wizard be causing an issue?