If receiving error 10102, try this.

It appears the issue with 10102 is brought on by a disconnection from the server. The server however believes your character is still logged in, therefore you are presented with this error.

Attempt 1: If you have a character on another server, attempt to login with that character.

IF you are met with 1017 errors.

Attempt 2: (The fix that worked for me) Roll a new character on an open JP server (for me this was Fenrir).

I went through the main cut scenes till I was able to see other players on the server (some have said this is not necessary). I then exited the game, logged back in through the launcher, and logged directly into my character (on Cactaur) without even seeing a 1017 (some may not be this lucky). If you however do see a 1017, this means it no longer thinks your character is logged in, which is a better sign than the 10102.

Did this and it does not work

Tried it and it doesnt work for me either.

I also tried it and doesn't work.

Same, made a toon on Titan after a short queue, logged and still incurring 10102. I imagine this will clear in time, and if there's naught that can be done that isn't already then likewise it does naught to pull hair in interest of health.

But such is this title's merit in-game... /le sigh

This worked for me too, made JP character, logged out after all the intro stuff and was able to immediately log into my NA character.

Didn't work for me.

Edit: just let me log in. Yay! I had to exit the game and come back for it to work.

I didn't pay money to get stuck at a log in screen for 6 hours... fix this now... have some respect for the people playing your game.. and get off your rears and fix the problem that prevents people from being able to play...

Love a very pissed off customer.