Is it possible to tell which email client customers use?

[albatroz]

Hello,
I was wondering if there is a way to sniff out the email messages my messages send
to tell the versions of the software my customers are using.
It happens that I have the impression that some of them are using very old versions
of Outlook that are forcing them to use unencrypted connections.

 

[LucasRolff]

Most clients will add their "signature" to the mail-headers what is used.

Can be added in the MIME-Version header, X-Mailer header or User-Agent header for example.

Outlook tends to put an X-Mailer header such as X-Mailer: Microsoft Outlook 16.0, and then it's just looking up the version here: Outlook versions, build numbers and other trivia - MSOutlook.info

 

[cPanelMichael]

Hello @albatroz,

Let us know if you have any additional questions.

Thank you.