Hi @emik85 ,

I've seen the same behavior once at a customer. We finally found out it had something to do with the Horizon client installation. The clients had been upgrade several times over the time from versions 4.x to 5.x. We fixed it by uninstalling the Horizon Client, removing any traces from the client from the registry and from the C-drive (program files, programdata), reboot and then reinstall the latest version. 

Hope this helps for you too.