Invalid credentiails. Invalid username or password

[Notit]

I will buy minecraft accaunt and want play in Technic Launcher, but i see a error: "Invalid credentiails. Invalid username or password ". But my friend can login with this password and login. Help please!

[EvilOwl]

He's giving you bad credentials.

Where can he login with that? To the vanilla launcher? To his own technic launcher? Does he have his credentials saved there? Maybe he doesn't remeber his own passwords, tell him to log out of his launcher and log in again to check who's wrong. You cannot be both logged in with the same credentials at the same time.