The message are displayed after updating a content type. The changed setting is the Publishing options -> Multilingual support -> Enabled, with field translation.

Screenshot
update content type error

I'm not sure if this is only a problem of Commerce Coupon.

Files: 

Comments

See
http://drupalcode.org/project/entity_translation.git/blob/refs/tags/7.x-...

The function entity_translation_menu_alter(), line 168 and the following, produces the message.

For a solution, please take a look at
http://drupal.org/node/1587108#comment-6180310

Category:bug» feature

There's no effort/testing in use entity translation with this module, so I'm not surprised you get some warnings there.

Not sure of what "base path" property is exactly but coupons should't have a uri normally.

@pcambra:

Entity translation relies on a 'base path' entity info key to provide the translation UI. It tries to provide a sane default but for non-default values it needs the module defining the entity to explicitly provide that info. See entity_translation.api.php.

See also #1114410: Replace hook_translation_info() with hook_entity_info(). The entity info is not changing but the hook in itself will go away.

Title:Entities of type Commerce Coupon do not define a valid base pathIntegrate with entity translation

Thanks for the comments plach, let's mark this as feature request and implement the same integration than for commerce products.