I had MariaDB installed on Ubuntu 16.04. Then tried to replace it with MySQL. After un-installing MariaDB now MySQL won't be install and I receive this error:
Errors were encountered while processing:
mysql-server-5.7
E: Sub-process /usr/bin/dpkg returned an error code (1)
I also run rm /etc/mysql /var/lib/mysql -r to delete configuration files, but no chance.
dbconfig-mysqlwas the only thing which solved the problem. – Omid Jun 15 '17 at 22:29