@Lisa
Have you looked at who you're getting a bounce back from?

Is this from an account who has recently edited their settings for emailed post notifications turned ON?

Is this from a new account?
edit: How are your new account settings -- are they set to default all new posts/Watch Lists are emails?
I believe "user #1" is the template for which all new registration settings are based off.


Are you sure the bounce back was related to a post? Rather, It could have been a PM notification.

Code
UPDATE `ubbt_USER_PROFILE` SET `USER_NOTIFY_ON_PM` = 'yes';

Furthering on what Gizmo posted above;
What was the result of your query when you ran it?

Code
0 row(s) affected by your query.

Did you run your query from the Database Tools > SQL Command screen within UBB.threads, or from an external SQL tool?
Your external tool may require also specifying a database name prior to the table name,

Did you take care in using the correct letter CASE of the tables which are in your database? They are case sensitive.

THIS:
Code
update ubbt_user_profile set user_email_watchlists = 0;

IS NOT THE SAME AS THIS:
Code
UPDATE `ubbt_USER_PROFILE` SET `USER_EMAIL_WATCHLISTS` = '0';

Further reading at:
https://www.ubbcentral.com/forums/ubbthreads.php/topics/196068/re-couple-of-questions#Post196068

---

ubbt_USER_PROFILE.USER_NOTIFY_ON_PM
should be be either yes or no

ubbt_USER_PROFILE.USER_EMAIL_WATCHLISTS
should be either 1 or 0

ubbt_USER_PROFILE.USER_ACCEPT_ADMIN_EMAILS
should be either On or Off

---

@Ruben
Blacklisting is mail provider specific. For example, emails to @aol.com and @hotmail.com addresses may always get sent to the recipient, @gmail.com may put you on to a blacklist. In addition, if you are not clear in your email footer about how to unsubscribe, a email host may automatically stick you on their blacklist, regardless if you only ever send a few items a day/week.

---

Some final words on emails / bounces / blacklisting...
Is the email server your' sending from using any type of security or encoding the messages before being sent? Or are you sending them from a plain text mailer?

How about your mail server; are you the only person sending from it? or are you on a shared mail server IP address, where others from the same hosting company are sending out emails from. It could be that those others are getting your addresses blacklisted as a spammer.

This could also be true for if you're on shared hosting and are placed on a box with 2,000 other accounts. Of which, a few accounts offer adult related content or "medications." You'd be classified in that same set also -- and possibly blacklisted. All because of the few accounts shared on the same box as you. Similar blacklisting could happen if the topics on your forums are of the "sensitive topics" categories.

Read the error message of the bounced items:
If they say, "Message flagged as spam" or "Message temporarily rejected," your message bounced because the email text or links look suspicious, or you could have added a large group of recipients to "CC" or "BCC." Remove links to websites asking for personal information.

If they say, "Recipient server did not accept our requests," its because your sending server isn't able to connect to the email server of your email's recipient. The problem usually goes away quickly without you doing anything. Try sending the email again later. If you keep getting the error, Check if there are any mistakes in the recipient's email address or contact the customer support team of your recipient's email provider. If you are sending to an address for a user who hasnt been active in a number of years, it could be that their email account has since been closed, especially If you got this error while emailing someone using a work, school, or other organization address. Again, if its important to have your message delivered to that person contact the addressee's administrator.

You may also want to have a look at Google's "Postmaster Tools" if you send a large volume of emails to Gmail users.
https://support.google.com/mail/answer/6227174
and their Bulk Senders Guidelines, which other services have similar guidelines for:
https://support.google.com/mail/answer/81126
Especially read through the "Authenticate your mail" section.


Current developer of UBB.threads PHP Forum Software
Current Release: UBBT 7.7.5 // Preview: UBBT 8.0.0
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