I know there is a simular question but it is marked as solved, which doesn't seem true anymore. I followed the advice to use the alternative installation. But I cann't go on in the installation process without specifing an accessable mirror. I do have actually internet accass from the machine in question but by a wifi adapter tp-link TL-WN725N which is not offered to configure during the installation process.
The question is, can I setup ubuntu 18.04 LTS on this machine in any way?
E.g. is there an "open shell" command on the setup menu which maybe allows me to configure the tp-link?
Or installing any other version of Ubuntu which is known to function with this hardware configuration and the downgrading(18.04 Desktop) or upgrading e.g. from 16.04 to 18.04 server?
Thank you for your time, Stephan