Getting encrypted name problem.

Great that you got it all sorted out. :-) Here are some intakes on your code.
I would make sure that you don't receive an error on mkdir. Exit and give the user an error. Or use a fallback folder and log it for an admin that you got an problem.

PHP Code:

mkdir('./assets/img/pets/' . $pet_entry_id, 0777, true); 


Same as the above, but only log it for the admin.

PHP Code:

rmdir('./assets/img/pets/' . $pet_entry_id); 


Where are you using this one? You are still saving "default_petavatar" correct?

PHP Code:

$errors = array('error' => $this->upload->display_errors()); 


Are this something critical for the user to see? Also that should be passed in flashdata() as you are doing a redirect later. If not log it for an admin.

PHP Code:

echo $this->image_lib->display_errors(); 


As far as I can tell this will never be seen. You are doing a redirect later on.

PHP Code:

$data = array('upload_data' => $this->upload->data()); 


Make sure this are returning true for success or false otherwise. If true = redirect. False = give user all those error messages you want.

PHP Code:

$this->pet_model->create_found_pet($image, $pet_entry_id); 


Thank you for pointing out the mistakes here! I'll recheck it and i will inform you as soon as i have any further issues! 

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