How do I create a fail loading screen

Now in game i have a loading screen,but when we host game this game can be not loaded(by any reasons).So i want to create a fail screen if we can load game.How to do that?

The problem here is that most times when a game doesn't load its either because of a browser incompatibility issue on user end, slow loading due to user connection, or an unexpected bug in your latest upgrade... only one of these you can control and easily detect... the last one.

No matter how cool of an event you make detecting load issues, if the game fails to load it will be moot.

I would focus on making a game that loads snappy with no bugs and make it look cool enough that users try another browser if they fail to load the first try.

But in any game,i think that a game with an error screen which explain error for user will be better.We need to catch some popular exceptions in some games right?