# X_OAUTH_PROVIDER_UNKNOWN

## Means

the URL named a provider this app has not enabled

## Typical cause

the `:provider` segment is not a known provider, **or** is one but was left out of `defineAuth({ providers })`; also `providerFor()` reaching for an id nothing registered. One refusal for all of them: distinguishing them would describe the app's configuration to an anonymous caller

## Fix

`registerOAuthProvider({ id: '<id>' })` if it is not built in, then add that id to `defineAuth({ providers: [...] })` — the registration comes **first** because a segment nothing registered cannot be added to `providers` at all, so "add it" alone was an instruction that could not be followed. The list the `fix` prints is what is **known here**, never the subset this app enabled, and `meta` carries only `{ provider }`

[Auth and sessions](/error-codes#auth-and-sessions)