ERR_TIMED_OUT when phpmailer ( i use ISPConfig ) send mail from PHP

Question

My phpmailer work correctly, in PHPMailer log i have message:

SERVER -> CLIENT: 250 2.0.0 Ok: queued as XXXXXXXXXXXXX

And I receive every email with small delay which is also OK.

But Every message (especially when I send more than 10 mails in the same time, but it is also visible when I send only 1 mail) make my server blocked for a while. In browser when I want to open my website I can see an error ERR_TIMED_OUT, putty, filezilla also doesn't work, just can't connect to the server.

Is there any log or something that could help diagnose the problem a bit? Or maybe someone had this stragne problem before me?

I have a small VPS server on which I installed ispconfig by myself

Thank you for all your replay

Answer 1

It is very likely that this is a rate/volume limit imposed by your hosting provider. I suggest you check their documentation about sending email through them, and use their support services if you have further questions.