# AUR0012

### **Error message**

Attempted to jitRegister an interface: `yyyy`

### **Parameters**

name (string)

### Error explanation

This error occurs when the DI container tries to automatically register (jitRegister) an interface key (created with `DI.createInterface`) that has not been registered and does not have a default implementation. The container cannot instantiate interfaces directly, so you must provide a registration or a default implementation.

### Common causes

* Calling `container.get(key)` with an interface key that has not been registered.
* Forgetting to register the interface or provide a default implementation when creating the interface.
* A plugin or library expected to register the interface did not do so.

### How to fix

* Register the interface with the container before calling `container.get(key)`.
* When creating the interface with `DI.createInterface`, provide a default implementation if appropriate.
* Double-check that the key used for registration matches the key used for resolution.
* If using plugins or libraries, ensure they are properly configured and registered.

### Debugging tips

* Check the stack trace to see where the resolution was attempted.
* Search your codebase for all registrations and resolutions of the interface key in question.
* If using plugins, try disabling them one at a time to isolate the source.

Please also note that this error could be caused by a plugin and not your application. After ruling out that the error is not being caused by your code, try removing any registered plugins one at a time to see if the error resolves itself.


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