By default, the application uses a registered earlier key (for single translations), which has daily and monthly limits. The daily request limit (per one API key) is 1,000,000 characters. The monthly limit is 10,000,000 characters.
For bulk translations you need to get your own FREE key on the activation page. If you do not have yandex account, please use this simple registration form. Getting the key will take you no more than 5 minutes and you can use the autotranslate function.
When you get a key, enter it in the appropriate field at the "Translate Feature" of the "Settings -> General" section menu.
If you want to increase the request limit, switch to the fee-based version of the yandex translate service.
Fees for using the paid service are listed on the Pricing page. If you agree to the fees, use the feedback form to send a request to switch to the fee-based version.