We need some more information, also Zoho requires the use of SSL when connecting. What kind of application or environment? You might not be using SSL in your connection.

What error are you receiving? you need to test port 465 availability like this

$ openssl s_client -starttls smtp -crlf -connect 204.141.24.118:465
CONNECTED(00000003)

Regarrrrrrrrrrds, pyrate ;0

Hello Guys, I have the same problem. I'm trying send e-mail from my application (PHPMailer) :

# telnet smtp.zoho.com 465
Time Out

# openssl s_client -starttls smtp -crlf -connect 8.40.222.118:465 
connect:errno=9

Same issue here. Can't ping or send emails via Zoho SMTP. This is a big issue and has been troubling us since weeks. Most probably digitalocean has blocked outgoing mails via Zoho..

I have enabled the port 465 by running:

ufw allow out 465

But still
telnet smtp.zoho.com 465 gives timeout and I cannot send the email. I can send the email from the local machine. Is this solved?? Any tips?

My ufw status verbose is as following:
WARN: / is group writable!
Status: active
Logging: on (low)
Default: deny (incoming), allow (outgoing), deny (routed)
New profiles: skip

To                         Action      From
--                         ------      ----
22                         LIMIT IN    Anywhere
80                         ALLOW IN    Anywhere
443                        ALLOW IN    Anywhere
465                        ALLOW IN    Anywhere
22 (v6)                    LIMIT IN    Anywhere (v6)
80 (v6)                    ALLOW IN    Anywhere (v6)
443 (v6)                   ALLOW IN    Anywhere (v6)
465 (v6)                   ALLOW IN    Anywhere (v6)

465                        ALLOW OUT   Anywhere
465 (v6)                   ALLOW OUT   Anywhere (v6)```

I found the solution

https://medium.com/@aungmt/sending-email-from-zoho-in-digital-ocean-40e93039c17d