Yii::$app->mailer->compose() Results In an "Unknown Property" error

When I run

Yii::$app->mailer->compose('signup', $params)

I receive the error:

Unknown Property

An internal server error occurred.

This works fine on my computer but gives that error on our production server. The config on production has the mailer defined and the same modules have been installed.

I cannot seem to get more details on the error.

Any idea what is causing this?

Figured this out. Wish there was a way to delete my post.

I wish more users posted an actual answer - even to their own question :sunny: