Last night I discovered that I could no longer send e-mail form my Gmail account. Whenever I sent a message it would bounce back with a “permanent failure” error related to SMTP authentication. Needless to say, this was very frustrating.
The full text of the error message was:
Google tried to deliver your message, but it was rejected by the recipient domain. We recommend contacting the other email provider for further information about the cause of this error. The error that the other server returned was: 535 535 5.7.3 Authentication unsuccessful (SMTP AUTH failed with the remote server) (state 7).
Background: Despite it’s shortcomings (e.g., this and this), I love Gmail. Thus, I have my work accounts set up to forward to my Gmail (technically Google Apps) account. However, I’m not a fan of my e-mail being marked as having been sent “on behalf of” my Gmail address when I send from my work address. I’ve therefore configured it to send through the SMTP server at work.
So… After beating my head against the wall for a bit, I decided to delete and re-enter the SMTP authentication details. It was at this point that I realized what had gone wrong. My employer’s mail system had forced me to change my password yesterday (we’re required to do this every year) and I had neglected to update the authentication details in my Gmail account. Duh!
Once I realized this, I updated the SMTP settings and everything was back to normal. Just thought I’d share this in case someone else runs into a similar problem in the future and isn’t sure what to do.