Hello,

We want ta add an additionnal header "List-Unsubscribe"

When we send several emails, we have to change the header "List-Unsubscribe" for each sended email (according to the recipient).

If we call AddHeader("List-Unsubscribe",xxx)

Does it erase the old header "List-Unsubscribe" or does it add a new header with the same name?

Best regards,

Florent

it erases old header and add the new header.