I have a similar problem.
When I try to send a message to a Google APPS email, I get this error message "450 4.1.1 ........" both Outlook (with or without ssl) as the Roundcube, but when I try to send the app mymail (android) messages are sent properly. This error occurs only for a domain where the mail server is Google Apps for domains other messages are sent properly.
This problem started about a week before that worked perfectly, do not know what else to try to solve.
Sorry for the English, I'm using Google translate.
When I try to send a message to a Google APPS email, I get this error message "450 4.1.1 ........" both Outlook (with or without ssl) as the Roundcube, but when I try to send the app mymail (android) messages are sent properly. This error occurs only for a domain where the mail server is Google Apps for domains other messages are sent properly.
This problem started about a week before that worked perfectly, do not know what else to try to solve.
Sorry for the English, I'm using Google translate.