hi
is it possible to play by internet with friends ?? Settlers 3 Ultimate Edition when i click Play By Internet , it ask me for Serial Number. i can`t find it, it is not on my GOG account

i love this game .how have to play by internet? thnk you for any help

ok . i did it .
support.gog.com/hc/en-us/articles/360008480314-Settlers-3-Ultimate-Collection-Game-asks-for-CD-Key-in-singlepl ayer-mode?product=gog
it works
now the main question . is S3 server still exists?

Yes, people use https://settlers-united.com/en/