junk mail: cannot add a 4 parts domain email to safe sender

[itamarh]

Anyone has any idea?
i get an email from (e-mail address removed).
the email is identified as spam.
i tried to add it to my safe senders list, but i get:
"the email address or domain name you entered is not valid. valied
entries include (e-mail address removed) or example.com."

i tried entering (e-mail address removed), c.d, etc. manually to the list, but it is
still not detected as a safe sender.

any ideas?

thanks.