Error while sending mail using PHP scripts

Problem: Got the following error while sending mail using php scripts.

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T=remote_smtp defer (-1): smtp transport process returned non-zero status 0x000b:
terminated by signal 11
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Then you can fix the issue by editing your /etc/exim.conf, and changing the following code:

----------------------
remote_smtp:
  driver = smtp
----------------------

To be,

----------------------
remote_smtp:
  driver = smtp
  hosts_avoid_tls=*
----------------------

Save exim.conf and restart exim.

If Exim is built with TLS support, and TLS is advertised by a server, the smtp transport always tries to start a TLS session. However, this can be prevented by setting hosts_avoid_tls (an option of the transport) to a list of server hosts for which TLS should not be used.

That's all.. :)