Is SMTP Allowed through Speedify?
Speedify blocks unencrypted SMTP (Simple Mail Transfer Protocol) on port 25 through Speedify. If you need to use SMTP, please use the SSL/TLS encrypted SMTP version on port 465 or 587.
This will not affect normal email users, since regular email programs don't use unencrypted SMTP any more.
Unfortunately, unencrypted SMTP is mostly used by spammers today, and allowing it gets our servers blocked by legitimate email providers.