Could not instantiate mail function

Quick Fix
Check that this error isn't resolved by just changing the Mailer (Joomla > Global Configuration > Mailer settings). Alternate between PHPmail and sendmail just to check this isn't the problem. If the problem is still there then check the below:

Tried both PHPmail and sendmail
So if this happens irrespective of whether I have PHP mail or sendmail set as the Mailer.
Could not execute: /usr/sbin/sendmail
Registration failed: An error was encountered while sending the registration email. A message has been sent to the administrator of this site.
  1.  Notice 
  2.  Could not execute: /usr/sbin/sendmail 
  3.  Warning 
  4.  Registration failed: An error was encountered while sending the registration email. A message has been sent to the administrator of this site. 
Check you can send email from that server
Message not sent. Server replied:
Connection refused
111 Can't open SMTP stream.
  1.  ERROR: 
  2.  Message not sent. Server replied: 
  3.  Connection refused 
  4.  111 Can't open SMTP stream. 

One common problem people have is an incorrectly setup mail system. Here is a list of rules that must be followed:
I took this from Direct Admin but it has some useful guidelines for these kind of issues:

How to setup the Mail System

1) hostname must not match any domain that is being used on the system. Example, if you have a domain called and you want to recieve mail on This email address is being protected from spambots. You need JavaScript enabled to view it., you must *not* set your hostname to We recommend using instead. You must make sure that you add the A record for so that it resolves.

2) The hostname must be in the /etc/virtual/domains file.

3) The hostname must *not* be in the /etc/virtual/domainowners file.

4) The hostname must resolve. If not, add the required A records to the dns zone such that it does.

5) The directory /etc/virtual/hostname must exist.. (eg: /etc/virtual/ It must not contain any files.

6) Any domains that you want to use for email (eg: must be in both the /etc/virtual/domains file and the /etc/virtual/domainowners file. The directory /etc/virtual/ must exist and the files /etc/virtual/ and /etc/virtual/ exist.

7) File permissions for virtual pop inboxes should be (not applicable with Dovecot/Maildir):
/var/spool/virtual/ 770 username:mail
/var/spool/virtual/* 660 username:mail

8) Ensure your hostname does not contain any upper case letters.

9) Make sure that your main server IP has a reverse lookup on it.
Category: Joomla :: Article: 358

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Joel Lipman

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