How to disable vbulletin sending e-mails to a certain user?

[postcd]

Hello,

i am receiving "Undelivered mail returning to sender" e-mails from time to time:

550 5.7.1 <member@email.here>: Recipient address rejected:
Recipient not found (in reply to RCPT TO command)

my hourly mail quota is limited so rather than trashing these e-mails i am trying to disable e-mail sending to such user in admincp

Editing user profile, this NOT helped:
- Receive Admin Emails (No)
- Users Awaiting Email Confirmation (ticking the tickbox)

My other non-tested/non verified ideas are:
- ban user (not ideal, not good for user, time consuming to ban and mention the reason)
- remove user e-mail address entirely and add to group Pending email confirmation (so user see message set for this group to explain that they need to change e-mail.)

[snakes1100]

Edit the user & turn off email notifications, remove subscribed threads, turn off friend notifications.

If they're active members, i put them in a secondary group & use the notice system to fix their email.

Edit user & delete the email in the account.

[postcd]

Do You mean that to prevent topic reply notification e-mail being sent, i have to remove user thread subscriptions? Because it is not good to do, since user may return, change e-mail, expecting notifications and not receiving these. I would have expected that Your suggestion "Edit user & delete the email in the account." would be enough.

i put them in a secondary group & use the notice system to fix their email.

Thanks, I have put a new notice for "Users Awaiting e-mail confirmation" group. /admincp/notice.php that user may need to change their e-mail and if unable to login (placing user to awaiting email confirmation group- i asked them to contact me with old/new email, i do not know if good idea or if i will be able to verify user is really the account owner)

[snakes1100]

Unfortunately yes, as the system is still going to try & send an email & itll bounce if they have active sub's.

If they arent active users & havent logged in for a year, they can resub to them, versus a server of mine getting dinged for spam.