Trouble replying to an email.

Support
1

Issue: Failed to Send Emails in K-9 Mail (Gmail via Yahoo)

Problem:

  • I tried replying to an email (sent from Gmail to my Yahoo) using K-9 Mail.
  • After hitting “Send,” I closed the app, but later got repeated notifications:

    “Failed to send some messages”

    • Debugging shows: “Retries exceeded” (using Yahoo Mail).
  • Previously, sending/receiving worked fine (I got a reply to an earlier email).
  • I haven’t changed any settings except enabling debugging and adjusting folders.

What I’ve Tried:

  • Searched for solutions but found nothing helpful.

Question:

  1. Why does it fail now if it worked before?
2

For your Yahoo account, go into the Sending Mail settings, select Outgoing server, click Next, and see if the connection goes through.

Repeat for Fetching Mail settings.

What is your Authentication choice for both Fetching and Sending set to?

1 Like
3

Hello, thanks for your reply.

  • Fetching and sending didn’t give any errors
  • OAuth 2.0 {was like this from the start}

also my error changed into “6.6.0 Error sending message for delivery” Yahoo mail isn’t showing this error, nor is fairemail so it’s k9 fault

4

That’s an odd response code. The ESMTP error codes typically follow a structured format of three numerical fields separated by dots, where the first digit indicates the class of the error (e.g., 2 for success, 4 for a transient negative, and 5 for a permanent negative). There are no codes that start with a 6.

Additionally, that text is not found in the application source code, so it is a message being returned by the server you have configured. If your provider offers support, you may want to ask them, as you may not find an answer here.