When you use the Photon Cloud instead of hosting yourself, there are a few additional error cases to keep in mind. These are explained below. Additionally, check the documentation included in the client platform SDKs for implementation details.
In all cases, the Photon Cloud Dashboard is useful to check the AppId and subscription.
The following errors happen during authorization with the cloud. The client is already connected but identifies the respective game by your AppId.
Authorization is done automatically when you call Connect (ConnectUsingSettings, or similar) in Photon Unity Networking and the various LoadBalancing-library implementations. Each client reference documentation explains the respective implementation in Connect.
This happens if the provided AppId is not known to the server at all. Check for typos and make sure you connect to the right server address.
CCU Limit Reached
Unless you have a plan with "CCU Burst", clients might fail the authentication step during connect.
Affected clients are unable to call operations. Please note that players who end a game and return to the master server will disconnect and re-connect, which means that they just played and are rejected in the next minute / re-connect.
This is a temporary measure. Once the CCU is below the limit, players will be able to connect an play again.
OpAuthorize is part of connection workflow but only on the Photon Cloud, this error can happen. Self-hosted Photon servers with a CCU limited license won't let a client connect at all.