My warm greeting to all techyv people , my post here is about my bad experience in sending an email using Thunderbird, an error will occur during sending mail, the error message goes unknown or illegal alias, please check the message recipients and try again.
An error occurred while sending mail. The mail servers responded: 5.1.1 unknown or illegal alias:
Please check the message recipients and try again.
As I read on the error message above, I am wondering why I got an error message regarding the address of the recipient, I am pretty sure its correct, it has been saved on my contacts, and I managed to send some email on past days using same address, that is why I am wondering on what went wrong this time, please share some comments on this issue, thanks.