Talk:Tutorial: Proxy Connection/@comment-26134970-20151201101034/@comment-26091666-20151201152739

That might be the reason why.. you're using another computer and probably because you use your gmail account and so perhaps DMM wants to setup something like TFA (Two Factor Authentication).

If it isn't that then you'll need to paste those texts that were in your screenshots (the ones in Japanese) like I mentioned before.