Sending emails
 

I was sending emails (~10K) last week, it was running smooth. I was done in 20 minutes. But now something happened (i dont know what) and it takes 2 minutes to send 5 emails.
Anyone know what's wrong?

Also does vBulletin uses SMTP or does it have built-in? How can I change it to my SMTP server?

You can't change vbulletin's mail settings very easily to suit yourself, or at least I can't, so it may be the fact that you are on a shared hosting server? Try sending them at different times to see if server load is the problem.

No, the server load is not the problem because the forums are hosted on a VPS.

Any other suggestions?

vBulletin Options -> Email Options

You can set an SMTP server to use in place of the default PHP mail() function.

Thanks..

Do you know what might be the reason why the emails are being sent very slow. It just happened this week, last week as I said that I sent around 10k emails in 20 minutes. Now it's taking hours...

Well if you're on shared hosting, the server's resources won't be fully available to just you, so sending out emails at different periods of activity can impact the speed.

I am on a VPS. Like I said, last week the emails were sent within 20 minutes. I can't even send 10 without waiting 5 minutes.

Seeing as your on a VPS, check your mail and http logs.

Is a 2MB mailque in mysql normal?