Is it possible to tell which email client customers use?

albatroz

Well-Known Member
Mar 6, 2003
350
3
168
Virtual Orbis / Peru
cPanel Access Level
Root Administrator
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.