Relevant Products: Exclaimer Cloud - Signatures for G Suite
Scenario
You are using Exclaimer Cloud, and start to receive bounce-backs from sent messages, with the following error;
535 5.7.8 Authentication credentials invalid [Response from smtp-relay.gmail.com was 534 5.7.14 https://support.google.com/mail/answer/78754 q6sm95039edh.25 - gsmtp]
Reason
This issue is caused by the SMTP authentication failing, when your messages attempt to proxy through our Cloud Solution and then back to G Suite.
Resolution
Most commonly this occurs when the user account used for the SMTP authentication process has an expired password, or the authentication attempts are being rejected due to throttling.
As the service also utilizes IP based authentication, we can now remove the SMTP credentials to resolve these issues without affecting the use of our service or your mail flow.
To do this, please follow the steps below:
Remove SMTP credentials from your tenant
- Login to Exclaimer Cloud here.
- Launch your subscription:
- Click the three-bar icon at the top right of the screen and select Settings:
- Select the Mail Flow tab, then click Edit:
- At the next screen, select the I have completed the setup in G Suite option and click Save
This will remove the previously saved credentials from the service and revert to the IP based authentication method.