On the service home page you must select your source OST file and fill out 2 mandatory fields: e-mail address and a Captcha code.
You will be sent a notification by e-mail when the conversion process is complete or if the conversion is interrupted with the URL of the page where you can continue the conversion.
When all the fields are filled in, you will be able to press the "Next Step" button. The OST file will now be uploaded to the service. The service will now display the status of the upload and conversion process.