[Koha] koha ugrade from 3.22.21 to 19.05.17

I've upgraded empty koha(on ubuntu 18.04) from 3.22.21 to 19.05.17 using only the tarball file(without sudo apt-get install koha-common). Everything was nice - until I tried to login intranet site with a super admin account after a successful web installer procedure of upgrading the koha tables: "Error: Invalid username or password". I checked the koha-conf.xml file and the username and password were unchanged! What happened with koha - did the Memcached server change the settings? George Mikuchadze National Scientific Library of Georgia