13.2 Wii U Error Viewer

[FearTheTJ]

Applications can use the Wii U Error Viewer to display the appropriate error message and error code for a returned error. As a rule, your application should use this Error Viewer to display errors.
Contact Nintendo support beforehand if you wish to change the display method (for example, to align with your application's look and feel). However, the application cannot implement its own display for all errors, because some errors cannot be displayed in the application (it is not possible to get the error code).
Note:
In general, libraries generate their own error codes, but in the case of communication errors there are APIs that return error codes from the server. Therefore, be aware that it is possible for communication errors to return unknown, currently undocumented error codes.
As long as you use the Error Viewer, there is no need for you to be aware of such cases because the Error Viewer handles the error messages for such cases automatically. However, if your application performs its own independent error display, make sure to display a general-purpose error message based on the general-purpose message from the "Communication-Related" section of the Error Code List.
13.2.1 Error Notification Method

Guideline Item
Applications must notify users of errors using the Wii U Error Viewer.
Test Method
Generate an error in the same relevant scenes as section 13.1.1 Handling Error Notifications, and check the error display.
Pass/Fail Determination
Passes if the application notifies the user of the error using the Wii U Error Viewer.
Software to Be Tested
All applications.