the invite button to my server in content manager does nothing

[micro$oft corp.]

i've spent all day setting up these convoluted servers. i forwarded ports, i did the hard bit. my server shows up to me and i can play on it. but my friend cannot find it. not by name, not by ip address, nothing. and the 'invite' button for my server in content manager does nothing at all.
why do we have to use technology from 1995 to play in private servers with friends?
there are 100s of issues from 100s of ppl and none of these random threads have had any answers. while there's over 4000 servers currently online.
do they just work for some ppl and not for others?
i have screenshots, logs all with no errors. what on earth am i missing?
thanks in advance but i'll bet this thread is added to the rest lol