Been having this problem only recently:
My launcher will just sit and do nothing when launching eve in 64bit. it will start the application but the window for the eve client never appears. when i go to launch another instance of eve it errors and comes up with “Cannot copy files for Tranquility while clients are running” and i have to manually kill the CCP ExeFile in task manager in order to launch the launcher with no apparent client running again (as i have no eve window to interact with).
when re-launching the launcher after killing the eve client (that never appears) in taskmanager, the launcher comes up seeming content that there’s no launcher or game update required. i ran a launcher network diagnostic test and all completed without issue.
the reason i KNOW its a 64bit client issue is if i uncheck ‘run clients with 64bit’, restart the launcher and start the game the CCP ExeFile opens from the 32bit bin folder and the client window appears promptly and i am able to play the game.
which is a bit of a shame cause if a big fight occurs then i will be unable to stream it to people as part of Talking in Stations and utilise my 3d mouse and full graphics to showcase EVE Online to twitch viewers without the ever present maximum ram ceiling client crash i always get with the 32bit client.