ISP's are now starting blocking email ports from other hosts.

vlee

Well-Known Member
Oct 13, 2005
373
26
178
Spokane, Washington
cPanel Access Level
Root Administrator
Just found out from some of my clients that ISP's are now starting blocking email ports from other hosts that are not the ISP's domains.

Ports that are being blocked are

SMTP Ports: 25, 587, Not sure about 465

POP3 Ports: 110, 995

IMAP Ports: 143, 993

SMTP is easy get around this issue in WHM. But how about POP3 and IMAP ports?

Centrylink was bought out by Quest so they are blocking ports from above. About 30% of my clients are having issues in get their email.
 

cPanelMichael

Administrator
Staff member
Apr 11, 2011
47,880
2,268
463
Hello :)

I suggest having the client contact the ISP to see if these ports can be unblocked. It's possible the ISP only blocks them by default, and will disable the block on a per-request basis.

Thank you.