Roblox error code 901: sign-in authentication failed

Error code 901 shows 'Authentication Error: trouble communicating with Roblox servers,' and it appears mainly on Xbox when signing in, signing up, or linking a gamertag to a Roblox account. Underneath the vague message there are a few real causes: Roblox servers having a bad moment, the account being under a moderation action, a gamertag that conflicts with Roblox naming rules during linking, or a corrupted app installation.

Fix it, in order

  1. Check Roblox's status page first. 901 spikes during platform incidents, and no local fix outruns an outage.
  2. Restart the app and the console fully (hold the Xbox power button for a full shutdown or use Restart), then sign in again. A stale session is a frequent one-off cause.
  3. Sign in to the same account on a phone or PC. If sign-in fails everywhere with a moderation notice, the account is restricted and only Roblox's appeals process applies. If it works elsewhere, the Xbox app is the problem.
  4. Unlink and re-link the account if linking triggers it, and check the gamertag itself: names that violate Roblox's naming rules can block the link with this code.
  5. Reinstall the Roblox app on the console if sign-in works elsewhere. A corrupted local install produces authentication failures that look like server trouble.

The moderation connection

Because 901 is an authentication verdict, an account under moderation can surface it instead of a clear notice, especially on console. That is why the cross-device sign-in test matters so much: it separates 'this app cannot authenticate' from 'this account may not authenticate,' and the two have completely different remedies, one a reinstall, the other an appeal.

Common questions

Is 901 a ban? Not necessarily, but it can be how a moderation action appears on Xbox. The test is signing in on another platform: a moderation notice there confirms it, while a clean sign-in means the console app or the servers were at fault.

Why does 901 mostly happen on Xbox? Xbox adds its own account layer (the gamertag) between you and Roblox, and the linking between the two is where this error lives. Sign-up and linking on console hit it far more than ordinary PC sign-ins.

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