Hi,

I've set up a catch-all email account that pipes into a PHP file - lets' call this *@test.hello.com which pipes to |/home/test/test.php

While majority of the servers work when you send to hello@test.hello.com. Some servers have their emails sent to hello@test.hello.com bounced.

Hi. This is the qmail-send program at xxxxxx.xxxxxxxx.com.
I'm afraid I wasn't able to deliver your message to the following addresses.
This is a permanent error; I've given up. Sorry it didn't work out.

<hello@test.hello.com>:
123.123.123.123 does not like recipient.
Remote host said: 550 No Such User Here"
Giving up on 123.123.123.123.
Why would there be a 550 error when it's suppose to be a catch-all address?

Could it be because of qmail? I don't have experience with qmail, but servers that worked used postfix when sending the emails.