How do I know that my email has been sent?

How can I prove that my email has been delivered?
4. Dezember 2017
Can I send „normal“ emails in addition to RMail?
4. Dezember 2017

How do I know that my email has been sent?

You will first receive a confirmation that your message is on its way to the recipient. Within 2 hours you will receive a receipt (Registered Receipt) proving where and when your email was delivered to the recipient. If the recipient has opened the email before you get the receipt, this is also apparent.