Uncaught Error: Class ‘SMTP’ not found in /usr/share/php/libphp-phpmailer/class

Hi Rob,

There is a very similar issue here: https://www.ads-software.com/support/topic/error-class-smtp-not-found/
That user had just to start with a fresh VM. Not a very helpful approach, but still.
So in general, your WordPress installation is using phpmailer packaged with your server, and not with WordPress itself.
PhpMailer class bundled with WP also has a reference to a SMTP class bundled with WP as well, so this is a dependency loading issue.
You may want to try to install WP differently, not using Softacolous or similar tools (if you have any) – in a different directory.

Hi @robscallsign – We haven’t heard from you in about a week, so I’m going to go ahead and mark this ticket resolved. If you still have questions, though, please feel welcome to continue the conversation.

Hey guys,

I have a similar issue to those above. I am running WordPress 4.9.12 on a VM and the installation included a global libphp-phpmailer package.

Has there been a better work around other than starting again with a fresh VM or a new WordPress install?

My error is:
PHP Fatal error: Uncaught Error: Class ‘SMTP’ not found in /usr/share/php/libphp-phpmailer/class.phpmailer.php:1495

I followed Slava’s advice and attempted to remove the package with:
sudo apt-get remove libphp-phpmailer

However it the info after the command told me that WordPress would be removed also so I did not remove it.

I renamed it and received this error:
PHP Fatal error: require_once(): Failed opening required ‘/usr/share/php/libphp-phpmailer/class.phpmailer.php’ (include_path=’.:/usr/share/php’) in /usr/share/wordpress/wp-content/plugins/wp-mail-smtp/src/MailCatcher.php on line 7

I then tracked down the specific line hoping to change the path to
/usr/share/wordpress/wp-includes/class-phpmailer.php

But received the same error (move down 2 lines with comments):
Fatal error: require_once(): Failed opening required ‘/usr/share/wordpress/wp-includes/class-phpmailer.php’ (include_path=’.:/usr/share/php’) in /usr/share/wordpress/wp-content/plugins/wp-mail-smtp/src/MailCatcher.php on line 9

Running on a Ubuntu 18.04 instance with ID_LIKE=debian

Any work around would be very helpful,

Thanks,

Matt

Just in case anyone else has issues with this, I have resolved the issue on my end. Although I can only speculate on its cause. The class.phpmailer.php in the libphp-phpmailer package and the class-phpmailer.php inside the wp-includes folder were identical and both threw the error at this function:

public function getSMTPInstance()
{
if (!is_object($this->smtp)) {
$this->smtp = new SMTP;
}
return $this->smtp;
}

Upon looking up class-phpmailer.php on the official WordPress github I noticed there was a new line of code in the function.

public function getSMTPInstance()
{
if (!is_object($this->smtp)) {
require_once( ‘class-smtp.php’ ); <–
$this->smtp = new SMTP;
}
return $this->smtp;
}

I have since added the line of code within my class.phpmailer.php inside my ibphp-phpmailer package and changed the name to class.smtp.php to match that within the package and my email test just succeed.

Thank you @mgtri for reporting back with your findings, very much appreciated!