Today i have a problem that an exchange will not send mails though TLS, no matter what i do.

I find out that, somehow this exchange servers where creating new send connector, with forcehelo = True.

Witch mean that the Exchange server is using the OLD HELO instead of the EHLO, when talking to other SMTP servers. Setting this to false help. Now the Exchange server send with TLS.

So FORCEHELO=$TRUE breaks TLS.

To see if this is the problem, you can type:

get-sendconnector | select id, forcehelo

To set it to false, for the send connector “Default_OUT” you can run this powershell command:

get-sendconnector -id Default_OUT | set-sendconnector -forcehelo $false

Also you might need to set the TLS certificate to the right certificate. Remember that the certificate need to have the hostname in the certificate. Se more on this link: