Thanks for your response
Firstly I cant download pi-hole using command curl -sSL https://install.pi-hole.net | bash. After this command I saw
!!! ERROR - Unable to update package cache. Please try “apt-get update”
apt-get update leads to
Hit http://archive.raspberrypi.org jessie InRelease
Hit http://mirrordirector.raspbian.org jessie InRelease
Ign http://giteduberger.fr rpimonitor/ InRelease
Hit http://giteduberger.fr rpimonitor/ Release.gpg
Hit http://giteduberger.fr rpimonitor/ Release
Hit http://mirrordirector.raspbian.org jessie/main armhf Packages
Hit http://giteduberger.fr rpimonitor/ Packages
Hit http://archive.raspberrypi.org jessie/main armhf Packages
Hit http://archive.raspberrypi.org jessie/ui armhf Packages
Ign http://giteduberger.fr rpimonitor/ Translation-en_GB
Ign http://giteduberger.fr rpimonitor/ Translation-en
Ign http://archive.raspberrypi.org jessie/main Translation-en_GB
Ign http://archive.raspberrypi.org jessie/main Translation-en
Ign http://archive.raspberrypi.org jessie/ui Translation-en_GB
Ign http://archive.raspberrypi.org jessie/ui Translation-en
W: Failed to fetch http://mirrordirector.raspbian.org/raspbian/dists/jessie/InRelease Unable to find expected entry 'universe/binary-armhf/Packages' in Release file (Wrong sources.list entry or malformed file)
E: Some index files failed to download. They have been ignored, or old ones used instead.
Then I opened /etc/apt/sources.list and made all lines commented (solution from this post ERROR - Unable to update package cache):
#deb Index of /raspbian jessie main universe contrib non-free rpi
#Uncomment line below then ‘apt-get update’ to enable ‘apt-get source’
#deb-src Index of /raspbian/ jessie main contrib non-free rpi
After this
sudo apt-get update
Hit http://archive.raspberrypi.org jessie InRelease
Ign http://giteduberger.fr rpimonitor/ InRelease
Hit http://giteduberger.fr rpimonitor/ Release.gpg
Hit http://archive.raspberrypi.org jessie/main armhf Packages
Hit http://giteduberger.fr rpimonitor/ Release
Hit http://giteduberger.fr rpimonitor/ Packages
Hit http://archive.raspberrypi.org jessie/ui armhf Packages
Ign http://giteduberger.fr rpimonitor/ Translation-en_GB
Ign http://archive.raspberrypi.org jessie/main Translation-en_GB
Ign http://archive.raspberrypi.org jessie/main Translation-en
Ign http://giteduberger.fr rpimonitor/ Translation-en
Ign http://archive.raspberrypi.org jessie/ui Translation-en_GB
Ign http://archive.raspberrypi.org jessie/ui Translation-en
Reading package lists… Done
And after this efforts to install pi-hole leads to the issue discribed in the topic