421 problem with outlook

[Jarita]

I ca receive emails but
Can NOT send
Get code 421
Can someone help a poor
Old man?

[BruceW]

We'd need the text that goes along with the error code, as 421 is associated with several different error conditions, ex:

• 421 - Too many sessions opened
• 421 - Reverse DNS failure
• 421 - Try again later

See https://postmaster.comcast.net/smtp-error-codes.php#421.

[BruceW]

---

@Jarita wrote: ... CSI IP 172.102.178.157 is not permitted to send messages. ...

---

CSI in the error message means the listed IP is blocked by Cloudmark Sender Intelligence. 172.102.178.157 is assigned to Ellijay Telephone Company / ETC Communications (see https://whois.arin.net/rest/net/NET-172-102-160-0-1). Please see https://forums.xfinity.com/t5/Email-Web-Browsing/Can-t-Send-Emails-from-PC-or-Phone-App/m-p/3355422#.... Are you using a VPN?

[Jarita]

not using VPN

[BruceW]

---

@Jarita wrote: not using VPN

---

Are you trying to send while using another ISP?