Unblock suspicious messages

Received a notice from Avast (Free ver.) of a message been blocked due to a suspicious attachment. How can I get such a message unblocked/released if I know the sender and am 100% sure it is safe (as well as extremely important to receive ???!)

is this a mail ?

Right click the tray icon and disable mail shield…

RECOMENDED: upload the attachment to www.virustotal.com and test it with 40+ malware scanners before you open it

Thanks Pondus! Yes it is a mail. I can not upload the attachment to www.virustotal.com, because I did’t receive it. This is what I want to achieve.

Regards

Well, if you’re 100% sure, you can change the mail shield settings for suspicious files.