Preventing piped email bounces

If you are piping emails into Kayako, but  your end users are getting a bounce back email with following error:

******************************************

This message was created automatically by mail delivery software.

A message that you sent could not be delivered to one or more of its recipients. 

This is a permanent error.

The following address(es) failed:

pipe to |/path/to/cli/index.phpgenerated by test@yourdomain.comlocal delivery failed

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You'll need to update the 'exim.conf' file to rectify the situation. Open 'exim.conf' and edit the following section:

address_pipe:
driver = pipe
return_fail_output

virtual_address_pipe:
driver = pipe
ignore_status
group = "${lookup{$domain}lsearch* {/etc/userdomains}{$value}}"
return_fail_output
user = "${lookup{$domain}lsearch* {/etc/userdomains}{$value}}"

Here, we have changed return_output to return_fail_output

The above shall resolve the email bounce back issue at the client's end.

In case the users shell is configured as jail shell, you need to suprress the error for jail shell as well i.e.

jailed_address_pipe:
driver = pipe
force_command
command = /usr/local/cpanel/bin/jailexec $address_pipe
return_fail_output

jailed_virtual_address_pipe:
driver = pipe
force_command
command = /usr/local/cpanel/bin/jailexec $address_pipe
user = "${lookup{$domain}lsearch* {/etc/userdomains}{$value}}"
group = "${lookup{$domain}lsearch* {/etc/userdomains}{$value}}"
return_fail_output

cagefs_address_pipe:
driver = pipe
force_command
command = /bin/cagefs_enter $address_pipe
return_fail_output

cagefs_virtual_address_pipe:
driver = pipe
force_command
command = /bin/cagefs_enter $address_pipe
user = "${lookup{$domain}lsearch* {/etc/userdomains}{$value}}"
group = "${lookup{$domain}lsearch* {/etc/userdomains}{$value}}"
return_fail_output