Germany:
https://en.wikipedia.org/wiki/Erfurt_school_massacre
https://en.wikipedia.org/wiki/Emsdetten_school_shooting
https://en.wikipedia.org/wiki/Winnenden_school_shooting
https://en.wikipedia.org/wiki/Heidelberg_University_shooting
https://en.wikipedia.org/wiki/Coburg_shooting
Finland:
https://en.wikipedia.org/wiki/Jokela_school_shooting
https://en.wikipedia.org/wiki/Kauhajoki_school_shooting
France:
https://www.bbc.com/news/world-europe-39292755
https://en.wikipedia.org/wiki/Toulouse_and_Montauban_shootin...
Spain:
https://en.wikipedia.org/wiki/Barcelona_school_killing
Estonia:
https://www.wsj.com/articles/estonia-school-shooting-leaves-...
Greece:
https://en.wikipedia.org/wiki/OAED_Vocational_College_shooti...
Hungary:
http://news.bbc.co.uk/2/hi/8380822.stm
Poland:
https://tvn24.pl/tvn24-news-in-english/poland-two-wounded-in...
Netherlands:
Ukraine:
https://en.wikipedia.org/wiki/Kerch_Polytechnic_College_mass...
Russia:
https://en.wikipedia.org/wiki/Perm_State_University_shooting
https://en.wikipedia.org/wiki/Kazan_school_shooting
https://en.wikipedia.org/wiki/2014_Moscow_school_shooting
https://siberiantimes.com/other/others/news/three-wounded-in...
Europe also has had the two deadliest mass shootings of all time: Bataclan (2015, 130 deaths) and Oslo (2011, 77 deaths).