problem with configuring SMTP credentials in argocd-notifications-controller. Getting 535 Authentication Credentials Invalid.

[karthiknannapaneni]

Logs: argocd-notifications-controller level=error msg="Failed to notify recipient email:xxxxxx.gmail.com defined in app argocd/test-app: 535 Authentication Credentials Invalid" app=argocd/test-app time="2020-08-25T22:14:53Z" level=info msg="Processing completed" app=argocd/test-app SMTP configuration: Secret: argocd-notifications-secret email: host: email-smtp.us-west-2.amazonaws.com port: 587 from: xxxxxxxxxxxx username: xxxxxxxxxxxxx password: xxxxxxxxxxxxxx https://argoproj-labs.github.io/argocd-notifications/services/overview/

[bartelsb]

I'm getting a similar error, but I think the issue is with the method of logging into the SMTP server, not specifically Argo. When I try to connect to our SMTP server via the SMTP protocol, the AUTH LOGIN command does not work. AUTH PLAIN is the only way I've been able to authenticate. I don't think Argo supports the AUTH PLAIN mechanism, and I don't know what's wrong with my use of the AUTH LOGIN mechanism (which passes the username and password separately). Anyone else running into this issue?