I installed OTOBO according to the provided docker installation manual. I added a new system address and tried sending an email from my private email account to it to see if the system actually receives tickets, they do not reach the ticketing system and I do not even receive an „undelivered email“ response from my mail provider.

When I try to send an email ticket to my private email from the ticketing system, I receive the following error message:

I am not sure what to make of this. How can I properly configure my client so I am able to send and receive messages to an email address of my choice?