phpMailer email not sending gmail smtp

Question

I am not able to send an email using gmail SMTP, this is what I'm getting when I print_r the object.

I'm using the same gmail credentials to Username and Password of phpMailer attributes, so I'm sure my credentials are correct but no idea why its not sending.

Thanks, appreciate any support.

EMailer Object
(
    [pathViews:protected] => application.views.email
    [pathLayouts:protected] => application.views.email.layouts
    [_myMailer:EMailer:private] => PHPMailer Object
        (
            [Priority] => 3
            [CharSet] => UTF-8
            [ContentType] => text/html
            [Encoding] => 8bit
            [ErrorInfo] => SMTP Error: Could not authenticate.
            [From] => support@qelasy.com
            [FromName] => Qelasy Administrator
            [Sender] => 
            [Subject] => Qelasy Security PIN
            [Body] => Dear Parent,<br /><br />You have successfully registered for Qelasy Security System.<br /><br />Please use this PIN to activate your tablet: <b>34123</b>.<br /><br />Thank you for registering with Qelasy Security System.<br /><br />We value your participation.<br /><br />If you have any questions please call +33 6 9881 1914 or email us at help@qelasy.com.<br /><br />Thank You,<br />Qelasy Security Team
            [AltBody] => 
            [WordWrap] => 0
            [Mailer] => smtp
            [Sendmail] => /usr/sbin/sendmail
            [PluginDir] => 
            [ConfirmReadingTo] => 
            [Hostname] => 
            [MessageID] => 
            [Host] => smtp.gmail.com
            [Port] => 465
            [Helo] => 
            [SMTPSecure] => ssl
            [SMTPAuth] => 1
            [Username] => appmonkeydev@gmail.com
            [Password] => ********
            [Timeout] => 10
            [SMTPDebug] => 
            [SMTPKeepAlive] => 
            [SingleTo] => 
            [LE] => 

            [smtp:PHPMailer:private] => SMTP Object
                (
                    [SMTP_PORT] => 25
                    [CRLF] => 

                    [do_debug] => 
                    [do_verp] => 
                    [smtp_conn:SMTP:private] => Resource id #86
                    [error:SMTP:private] => 
                    [helo_rply:SMTP:private] => 250-mx.google.com at your service, [220.247.236.99]
250-SIZE 35882577
250-8BITMIME
250-AUTH LOGIN PLAIN XOAUTH XOAUTH2 PLAIN-CLIENTTOKEN
250-ENHANCEDSTATUSCODES
250-CHUNKING
250 SMTPUTF8

                )

            [to:PHPMailer:private] => Array
                (
                    [0] => Array
                        (
                            [0] => azraarshu@gmail.com
                            [1] => 
                        )

                )

            [cc:PHPMailer:private] => Array
                (
                    [0] => Array
                        (
                            [0] => yohan@appmonkeyz.com
                            [1] => Yohan Hirimuthugoda
                        )

                    [1] => Array
                        (
                            [0] => azraar@app-monkeyz.com
                            [1] => Azraar Azward
                        )

                )

            [bcc:PHPMailer:private] => Array
                (
                )

            [ReplyTo:PHPMailer:private] => Array
                (
                    [support@qelasy.com] => Array
                        (
                            [0] => support@qelasy.com
                            [1] => 
                        )

                )

            [all_recipients:PHPMailer:private] => Array
                (
                    [azraarshu@gmail.com] => 1
                    [yohan@appmonkeyz.com] => 1
                    [azraar@app-monkeyz.com] => 1
                )

            [attachment:PHPMailer:private] => Array
                (
                )

            [CustomHeader:PHPMailer:private] => Array
                (
                    [0] => Array
                        (
                            [0] => Cc
                            [1] =>  Yohan Hirimuthugoda <yohan@appmonkeyz.com>
                        )

                    [1] => Array
                        (
                            [0] => Cc
                            [1] =>  Azraar Azward <azraar@app-monkeyz.com>
                        )

                )

            [message_type:PHPMailer:private] => plain
            [boundary:PHPMailer:private] => Array
                (
                    [1] => b1_631af702e0f737dd5c11dcff55e1d8ee
                    [2] => b2_631af702e0f737dd5c11dcff55e1d8ee
                )

            [language:protected] => Array
                (
                    [provide_address] => You must provide at least one recipient email address.
                    [mailer_not_supported] =>  mailer is not supported.
                    [execute] => Could not execute: 
                    [instantiate] => Could not instantiate mail function.
                    [authenticate] => SMTP Error: Could not authenticate.
                    [from_failed] => The following From address failed: 
                    [recipients_failed] => SMTP Error: The following recipients failed: 
                    [data_not_accepted] => SMTP Error: Data not accepted.
                    [connect_host] => SMTP Error: Could not connect to SMTP host.
                    [file_access] => Could not access file: 
                    [file_open] => File Error: Could not open file: 
                    [encoding] => Unknown encoding: 
                    [signing] => Signing Error: 
                    [smtp_error] => SMTP server error: 
                    [empty_message] => Message body empty
                    [invalid_address] => Invalid address
                    [variable_set] => Cannot set or reset variable: 
                )

            [error_count:PHPMailer:private] => 1
            [sign_cert_file:PHPMailer:private] => 
            [sign_key_file:PHPMailer:private] => 
            [sign_key_pass:PHPMailer:private] => 
            [exceptions:PHPMailer:private] => 1
        )

)

Email received from Gmail.

Hi appmonkey, 

We recently blocked a sign-in attempt to your Google Account [appmonkeydev@gmail.com]. 

Sign in attempt details
Date & Time: Tuesday, August 26, 2014 9:23:38 AM UTC 
Location: Colombo, Sri Lanka 

If this wasn't you
Please review your Account Activity page at https://security.google.com/settings/security/activity to see if anything looks suspicious. Whoever tried to sign in to your account knows your password; we recommend that you change it right away. 

If this was you
You can switch to an app made by Google such as Gmail to access your account (recommended) or change your settings at https://www.google.com/settings/security/lesssecureapps so that your account is no longer protected by modern security standards. 

To learn more, see https://support.google.com/accounts/answer/6010255. 

Sincerely,
The Google Accounts team

Answer 1

Check your Gmail / Accounts & Import / Other Google Account Settings

Some apps and devices use less secure sign-in technology, which makes your account more vulnerable. You can turn off access for these apps, which we recommend, or turn on access if you want to use them despite the risks. Learn more

Access for less secure apps Turn off Turn on

Change to "Turn on"

Had the same problems but now it works for me.

Answer 2

I oftent faced this problem, GMAIL does not allow to send email using script. Login and check the email you are using in code to see if you get notice of malicious activity on your account. If yes then, I solved this issue by loging in the GMAIL from my HOST and allowing it to send mail using the email.

Not sure this is applicable to your problem