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Error code "550 DKIM Sender Invalid" from only one receiver

Thunderbird Troubleshooting
Googlethunderbird. replied
nyjmc
nyjmc

I use RCN as my ISP. There is an email address I have been sending to successfully for years, but recently all my emails to it are rejected. The error message I get is

550 DKIM Sender Invalid - envelope rejected - https://community.mimecast.com/docs/DOC-1369#550 [fCBPAkhbPf-Iq3bdFn4emA.us643]

Can you help me get this fixed?

Thanks, Jim M

I use RCN as my ISP. There is an email address I have been sending to successfully for years, but recently all my emails to it are rejected. The error message I get is 550 DKIM Sender Invalid - envelope rejected - https://community.mimecast.com/docs/DOC-1369#550 [fCBPAkhbPf-Iq3bdFn4emA.us643] Can you help me get this fixed? Thanks, Jim M

All Replies (2)

david
david
  • Top 10 Contributor

This is a security error and that email host has tighter restrictions than the other emaill providers to whom you send email. This issue needs to be referred to your email provider, unless you use a self-hosted email, in which you may be the one to fix it. This is a server setting, not something within Thunderbird.

Googlethunderbird.
Googlethunderbird.
  • Top 25 Contributor

Hello there We have read the question We try to help you

Your code consists of stating that you are using an unknown domain name, that is whether this cause gets you there okay and if you are using an invalid domain name and you should check it if you can.

This has been broken or removed from your activities.

Actual sources are about your topic, your listed code is equally related to an immediate failed update of the common topic you were mentioned, the task is to restore all the tasks of this one and reactivate your authentication with singering, which can take quite some time before this is activated, again whether you can perform this in Thunderbird is the second question?

Greetings Firefox volunteer