I have admin rights for Google Apps on our domain. Recently an employee left the firm. Rather than delete his Google account, I just disabled his rights to use GMail. This worked. His account can no longer be used to access GMail. Yet when I send mail to his GMail account, I don't receive a bounce-back (NDR - non-deliverable). Why is this? I'd prefer that those who send email to this old account get a bounce-back so they don't assume that their email was delivered successfully. Any ideas?
Removing access is not the same as removing the email. The email account still exists, they just can't access it. So emails are collecting in the inbox. If you enable access and log in, you will see them. To get a message to bounce, you have to remove the email account entirely. If you managed your own mailbox server, for example Postfix, then you could probably set an option or filter to bounce even if the account existed. However, for web-based mail, you won't have that level of control.
How did you "disable his rights"? Suspending the account is the best approach.
You do not need to remove the email account or even change the password. (best practice is to change the password though)
When you Suspend an account in the Google Apps Domain Manager, all future messages sent to that account are rejected with the following error message:
Delivery to the following recipient failed permanently:
Technical details of permanent failure: Google tried to deliver your message, but it was rejected by the server for the recipient domain domain.com by aspmx.l.google.com. [ip address].
The error that the other server returned was: 550 5.2.1 The email account that you tried to reach is disabled. 6311373vfb.420 - gsmtp
Suspend a user notes:
If the user has shared any documents, sites, or secondary calendars, these shared assets are still accessible to collaborators.
A suspended user cannot sign in to his or her account, and new information, such as emails and calendar invitations, are blocked.
To suspend a user:
Find the user account and open it.
In the new Admin console, click the pull-down menu under the user's picture and select Suspend user.
In the classic Admin console, click Suspend user in the top right.
Click ok in the confirmation box.
To confirm that a user is suspended, click Users and check the Status column to see if the user is marked as Suspended.