Applications » Cannot Sign in to Application Loader

Hi, I have fianlly finished developing our AIR app, and we're trying to submit the IPA file to Testflight (and eventually the store) via Application Loader.

For some infuriating reason, I keep getting the error: "Your Apple ID or password was entered incorrectly" even though I am 100% certain that my credentials are correct.

After resetting my password, the problem persists.

I then tried signing in with my colleague's Apple ID, and it is fine, BUT as soon as we add that colleague to the iTunes Connect account and Apple Developer team, the password fails again!

This is very strange, and as silly as it sounds, I think it is something to do with the team member or role permissions that is affecting the sign-in process, can anyone please help? We're so close to releasing the app!!!

UPDATE:
After trying to log in with Application loader on another developer's machine running the latest Mac OS, we're getting a different error message: "Your Apple ID account is also attached to other iTunes providers." Sounds like the adding/removing of roles and team memberships could be the cause of this issue? Argh! Am I doing something wrong?


Thank You!!!


I didn't find the right solution from the Internet.
References
https://forums.developer.apple.com/thread/35342
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