Public Domain Name Servers

This comes in handy if the SMTP server isn't an open relay, or when traveling and accessing the Web via different ISPs.
Just configure the SMTP server (Free SMTP is free) with the DNS field set to one of the IP addresses below.

Public (Level3) Name servers (these are OC192's)
4.2.2.1
4.2.2.2 (fast)
4.2.2.3
4.2.2.4
4.2.2.5
4.2.2.6 (fast)

Open to the Public
# ns1.la.us.opennic.glue (New Orleans, LA, US) - 68.15.165.12
# ns1.phx.us.opennic.glue (Phoenix, AZ, US) - 63.226.12.96
# ns1.sfo.us.opennic.glue (San Francisco, CA, US) - 64.151.103.120 (fast)
# ns1.co.us.opennic.glue (Longmont, CO, US) - 216.87.84.209

SpeakEasy Name servers
66.93.87.2
216.231.41.2
216.254.95.2
64.81.45.2
64.81.111.2
64.81.127.2
64.81.79.2
64.81.159.2
66.92.64.2
66.92.224.2
66.92.159.2
64.81.79.2
64.81.159.2
64.81.127.2
64.81.45.2
216.27.175.2
66.92.159.2
66.93.87.2

Sprintlink General DNS
204.117.214.10
199.2.252.10
204.97.212.10

Cisco
128.107.241.185
192.135.250.69