Error 113 while installing Lightroom classic

Hi all,

I just bought the bundle "Photo-Abo" (german site) and I am trying to install Lightroom classic. After succesful installation of the CC-Desktop the installation of Lightroom classic crushes below 10%.  I repeated several times trying out some possibilities. This is what I did until now.

- tried to install LrC as normal windows user as administrator

- tried to install LrC logged in as administrator

- both trials having the antivirus software (Avast) switched on (while watching if any app is blocked - it isn't), but also swithed off.

- internet connection is stable - 100 MB/s

- using Win 11

- I have restarted my PC for several times

- I resetted winsock

- I signed out and in for several times

- for information: Lighroom classic v 6 is installed on this PC (the version I worked until now)

Please help!

Thanks in advance, Hans!