ArcGIS Javascript API query only returning max 500 features?

If you are performing a query or identify using the ArcGIS Server API, and the map service is only returning a maximum of 500 features when the query should be returning more, this is by design.

The limit on features returned is because of a default REST endpoint limit established for each map service of 500. This setting is stored in your map service configuration file, generally located at C:\Program Files\ArcGIS\server\user\cfg\[ServiceName].MapServer.cfg, as 500.

You can override this setting, and the map service will return as many features as you like, however, you should consider the amount of data that your client will be forced to download. The more features returned, the longer it will take to download them to the client, thus resulting in slower perfoming websites.