While developing an iOS application with Push Notification, there might be a time, one comes across the following error message.

- no valid 'aps-environment' entitlement string found for application

Well, that means the APN (Apple Push Notification) server is denying to register your application. This situation arises when the signing certificate for the application differs from the one you generated for Push Notification.

The fix is to select the proper certificate in the settings for the project.

Happy coding.