Hi Christoph Spaniol,
in your log - file, you will find as first error:
Code:
E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution).
If you executed the command "
apt-get -f install", please consider to inform us about the output from your command line, for further investigations, even that your provided log already points to apt-get - dependencies errors.
When you update/upgrade packages on Debian/Ubuntu - based systems, please be informed, that using "aptitude" instead of "apt-get", may help to solve dependencies easily, because "aptitude" could be used to automatically search for different solutions ( different update/upgrade/downgrade/un-install and install - options will be shown, if you don't like the first option and desire to choose another one over the command line, using the "no" - option after each suggestion from "aptitude" ).
To inform yourself about the advantages using aptitude, please have a look at the following link ( I choosed a german text-based link, according to yoiur log... ^^ ):
The main cause of your errors at the moment is, that you already installed MySQL - server - version 5.5.46, but the dependencies are based on the version 5.5.44.
Code:
mysql-server-5.5 : Depends: mysql-client-5.5 (>= 5.5.46-0+deb7u1) but 5.5.44-0+deb7u1 is to be installed
Depends: mysql-server-core-5.5 (>= 5.5.46-0+deb7u1) but 5.5.44-0+deb7u1 is to be installed
PreDepends: mysql-common (>= 5.5.46-0+deb7u1) but 5.5.44-0+deb7u1 is to be installed
Breaks: mysql-server (< 5.5.46-0+deb7u1) but 5.5.44-0+deb7u1 is to be installed
MySQL version 5.5.46 was recently ( 25.10.2015 ) accepted to be moved to stable-sec ( stable security ), but didn't find its way yet to all stable sources. You could now wait some days, or solve the cause by downgrading MySQL back to 5.5.44, so that all dependencies are met.