I’m using PHPMailer in a Simple Script For Send Email’s Through Gmail, and I’m getting an «Unknown Error» (At least for me!):
SMTP Error: Could not authenticate.
Error: SMTP Error: Could not
authenticate.SMTP server error: 5.7.1 Username and
Password not accepted. Learn more at
535 5.7.1
http://mail.google.com/support/bin/answer.py?answer=14257
p38sm2467302ybk.16
I’ve read about Configure OpenSSL For SSL/TLS Connections, and I did it. Apache And PHP Are properly-Configured (With OpenSSL extension Running in PHP and mod_ssl running in Apache 2.2.16).
This is The PHP Script:
<?php
require_once ("PHPMailerclass.phpmailer.php");
$Correo = new PHPMailer();
$Correo->IsSMTP();
$Correo->SMTPAuth = true;
$Correo->SMTPSecure = "tls";
$Correo->Host = "smtp.gmail.com";
$Correo->Port = 587;
$Correo->UserName = "foo@gmail.com";
$Correo->Password = "gmailpassword";
$Correo->SetFrom('foo@gmail.com','De Yo');
$Correo->FromName = "From";
$Correo->AddAddress("bar@hotmail.com");
$Correo->Subject = "Prueba con PHPMailer";
$Correo->Body = "<H3>Bienvenido! Esto Funciona!</H3>";
$Correo->IsHTML (true);
if (!$Correo->Send())
{
echo "Error: $Correo->ErrorInfo";
}
else
{
echo "Message Sent!";
}
?>
The Username and Password are OK, And I tried in Thunderbird, without any problem.
I’ve also Used SSL Authentication and Port 465, getting the same Error.
Cœur
36.4k25 gold badges191 silver badges259 bronze badges
asked Oct 16, 2010 at 16:57
2
I encountered this problem. To get it working, I had to go to myaccount.google.com -> «Sign-in & security» -> «Apps with account access», and turn «Allow less secure apps» to «ON» (near the bottom of the page).
Alternatively you can follow this direct link to these settings
Joundill
6,42211 gold badges35 silver badges50 bronze badges
answered Sep 4, 2015 at 14:56
7
Try this instead :
$Correo->Username = «foo@gmail.com»;
I tested it and its working perfectly without no other change
answered Oct 16, 2010 at 17:19
malletjomalletjo
1,78616 silver badges18 bronze badges
2
I received the same error and in mycase it was the password. My password has special characters.
If you supply the password without escaping the special characters the error will persist.
E.g $mail->Password = " por$ch3"; is valid but will not work using the code above .
The solution should be as follows: $mail->Password = "por$ch3";
Note the Backslash I placed before the dollar character within my password.
That should work if you have a password using special characters
answered Aug 1, 2012 at 9:57
BubbaBubba
1011 silver badge7 bronze badges
2
Because Allow less secure apps is no longer available
The solution was to enable 2-step verification and generate app password
select mail and computer from the list then click generate
copy the code shown in the box and replace your google password with your app password it works like a charm.
answered Jun 28, 2022 at 2:10
Kym NTKym NT
6309 silver badges28 bronze badges
1
I experienced the same error when configuring the WP-Mail-SMTP plugin in WordPress.
The problem would persist even when I have ‘triple checked’ the settings and login credentials, and am able to log in manually using a browser.
There’s a list of steps you can take to fix this.
- Create a new password for the Gmail account you want to use
- Enable less secure apps in Google Security settings
- Use the
Display Unlock Captchapage to give your app or website permission to sign in to Gmail. ClickContinueor follow the instructions. - Sign in using the app or website. The smtp settings that work for me are 1) SMTP Host: smtp.gmail.com 2) SMTP port: 587 3) Encryption: TLS 4) Authentication: SMTP authentication 5) Username: example@gmail.com 6) Password: examplesecret
Greg
20.9k17 gold badges81 silver badges106 bronze badges
answered Jul 20, 2017 at 8:24
pyforkpyfork
3,5972 gold badges20 silver badges18 bronze badges
1
my solution is:
- change gmail password
- on gmail «Manage your google Account» > Security > Turn on 3rd party app Access
- This the new step that i discover by UnlockingCaptcha that told in this site, the exact site is https://accounts.google.com/b/0/DisplayUnlockCaptcha, but maybe you want to read the former site first.
That all, hope it works for you
answered Jul 15, 2020 at 15:37
1
I received this error because of percentage signs in the password.
answered Dec 5, 2011 at 13:22
svandragtsvandragt
1,61320 silver badges37 bronze badges
1
For me I had a special characters in my password field, and I put it like $mail->Password = » por$ch3″ which work for gmail smpt server but not for other; so I just changed double quotes to single quotes and it works for me. $mail->Password = ‘ por$ch3’;
answered Jun 11, 2013 at 12:17
3
If you still face error in sending email, with the same error message. Try this:
$mail->SMTPSecure = 'tls';
$mail->Host = 'smtp.gmail.com';
just Before the line:
$send = $mail->Send();
or in other sense, before calling the Send() Function.
Tested and Working.
answered Jun 11, 2014 at 19:30
JackSparrowJackSparrow
9081 gold badge11 silver badges8 bronze badges
1
The other post is correct to resolve the issue but doesn’t address how to do it if the 2-step-verification is turned on. The option to allow the less secure apps is NOT available then. Here is an answer to how to do it:
a. Go to the URL of `https://myaccount.google.com/` and click `Sing-in and security`
b. Click on the app password.
You will reach a page like this,
c. Create name of your app and generate a password for the respective app.
d. Use that password acquired here inside the app.
This should resolve the issue.
answered May 20, 2018 at 10:16
ArefeArefe
10.4k16 gold badges101 silver badges159 bronze badges
0
I had the same issue and did all the tips including Gmail setting (e.g. less secure apps access) with no luck. But finally when I changed password to something different, for some reason it worked! FYI, the initial password did not have any special characters.
answered May 24, 2016 at 22:57
EhsanEhsan
1,02211 silver badges20 bronze badges
- first go to https://myaccount.google.com
- Select Security tab
- Scroll down and select ‘Less secure app access’
- Turn on access
This will solve my “SMTP Error: Could not authenticate” in PHPMailer error.
answered Apr 29, 2020 at 13:07
ruwanmadhusankaruwanmadhusanka
7812 gold badges7 silver badges15 bronze badges
I had the same issue and did all the tips with no luck. Finally when I changed password to something different, for some reason it worked! (the initial password or the new one did not have any special characters)
answered Aug 18, 2019 at 14:06
0
The correct answer:
Go to «Manage your google accounts => Security => Signing in to Google => App passwords».
Generate your maill account password there (that will be used from other device)
answered Apr 13, 2022 at 9:49
I had the same problem with authentication. The fix was to set up 2-step verification and create an application specific password for the device ( error messages for blocking the device will appear in your account settings->»Notifications and alerts» if you problem is the same with mine)
answered Jan 29, 2015 at 21:35
It was the selinux issue. I just updated the below given part in /etc/selinux/config file
SELINUX=permissive (it was SELINUX=enforcing before).
then just reboot the system by giving
reboot
Now the mail goes without any hassle.
Configuration
From Email Address : [noreply@yourdomain.com]
From Name : [your domain name]
SMTP Host : smtp.gmail.com
Type of Encryption : SSL
SMTP Port : 465
SMTP Authentication : YES
Username : [your mail id]
Password : [your password]
answered Feb 10, 2016 at 7:17
SMTP Error: could not authenticate
I had the same problem. The following troubleshooting steps helped me.
- I turned off two-factor authentication in my gmail account.
- I allowed less secure apps to access my gmail account. To get it working, I had to go to
myaccount.google.com->Sign-in & security->Apps with account access, and turnAllow less secure appstoON(near the bottom of the page). - At this step, when I tried to register a user, I would get the same error. Google would sent me a warning message that someone has my password and the login was blocked.
- Gmail will then provide you with options. You either click whether the activity was yours or not yours. Click the option that the activity was yours.
- Try registration again. It should now work.
cSteusloff
2,4376 gold badges27 silver badges50 bronze badges
answered Dec 14, 2017 at 11:47
There is no issue with your code.
Follow below two simple steps to send emails from phpmailer.
You have to disable 2-step verification setting for google account if you have enabled.
Turn ON allow access to less secure app.
answered Apr 12, 2018 at 7:24
I’m using PHPMailer in a Simple Script For Send Email’s Through Gmail, and I’m getting an «Unknown Error» (At least for me!):
SMTP Error: Could not authenticate.
Error: SMTP Error: Could not
authenticate.SMTP server error: 5.7.1 Username and
Password not accepted. Learn more at
535 5.7.1
http://mail.google.com/support/bin/answer.py?answer=14257
p38sm2467302ybk.16
I’ve read about Configure OpenSSL For SSL/TLS Connections, and I did it. Apache And PHP Are properly-Configured (With OpenSSL extension Running in PHP and mod_ssl running in Apache 2.2.16).
This is The PHP Script:
<?php
require_once ("PHPMailerclass.phpmailer.php");
$Correo = new PHPMailer();
$Correo->IsSMTP();
$Correo->SMTPAuth = true;
$Correo->SMTPSecure = "tls";
$Correo->Host = "smtp.gmail.com";
$Correo->Port = 587;
$Correo->UserName = "foo@gmail.com";
$Correo->Password = "gmailpassword";
$Correo->SetFrom('foo@gmail.com','De Yo');
$Correo->FromName = "From";
$Correo->AddAddress("bar@hotmail.com");
$Correo->Subject = "Prueba con PHPMailer";
$Correo->Body = "<H3>Bienvenido! Esto Funciona!</H3>";
$Correo->IsHTML (true);
if (!$Correo->Send())
{
echo "Error: $Correo->ErrorInfo";
}
else
{
echo "Message Sent!";
}
?>
The Username and Password are OK, And I tried in Thunderbird, without any problem.
I’ve also Used SSL Authentication and Port 465, getting the same Error.
Cœur
36.4k25 gold badges191 silver badges259 bronze badges
asked Oct 16, 2010 at 16:57
2
I encountered this problem. To get it working, I had to go to myaccount.google.com -> «Sign-in & security» -> «Apps with account access», and turn «Allow less secure apps» to «ON» (near the bottom of the page).
Alternatively you can follow this direct link to these settings
Joundill
6,42211 gold badges35 silver badges50 bronze badges
answered Sep 4, 2015 at 14:56
7
Try this instead :
$Correo->Username = «foo@gmail.com»;
I tested it and its working perfectly without no other change
answered Oct 16, 2010 at 17:19
malletjomalletjo
1,78616 silver badges18 bronze badges
2
I received the same error and in mycase it was the password. My password has special characters.
If you supply the password without escaping the special characters the error will persist.
E.g $mail->Password = " por$ch3"; is valid but will not work using the code above .
The solution should be as follows: $mail->Password = "por$ch3";
Note the Backslash I placed before the dollar character within my password.
That should work if you have a password using special characters
answered Aug 1, 2012 at 9:57
BubbaBubba
1011 silver badge7 bronze badges
2
Because Allow less secure apps is no longer available
The solution was to enable 2-step verification and generate app password
select mail and computer from the list then click generate
copy the code shown in the box and replace your google password with your app password it works like a charm.
answered Jun 28, 2022 at 2:10
Kym NTKym NT
6309 silver badges28 bronze badges
1
I experienced the same error when configuring the WP-Mail-SMTP plugin in WordPress.
The problem would persist even when I have ‘triple checked’ the settings and login credentials, and am able to log in manually using a browser.
There’s a list of steps you can take to fix this.
- Create a new password for the Gmail account you want to use
- Enable less secure apps in Google Security settings
- Use the
Display Unlock Captchapage to give your app or website permission to sign in to Gmail. ClickContinueor follow the instructions. - Sign in using the app or website. The smtp settings that work for me are 1) SMTP Host: smtp.gmail.com 2) SMTP port: 587 3) Encryption: TLS 4) Authentication: SMTP authentication 5) Username: example@gmail.com 6) Password: examplesecret
Greg
20.9k17 gold badges81 silver badges106 bronze badges
answered Jul 20, 2017 at 8:24
pyforkpyfork
3,5972 gold badges20 silver badges18 bronze badges
1
my solution is:
- change gmail password
- on gmail «Manage your google Account» > Security > Turn on 3rd party app Access
- This the new step that i discover by UnlockingCaptcha that told in this site, the exact site is https://accounts.google.com/b/0/DisplayUnlockCaptcha, but maybe you want to read the former site first.
That all, hope it works for you
answered Jul 15, 2020 at 15:37
1
I received this error because of percentage signs in the password.
answered Dec 5, 2011 at 13:22
svandragtsvandragt
1,61320 silver badges37 bronze badges
1
For me I had a special characters in my password field, and I put it like $mail->Password = » por$ch3″ which work for gmail smpt server but not for other; so I just changed double quotes to single quotes and it works for me. $mail->Password = ‘ por$ch3’;
answered Jun 11, 2013 at 12:17
3
If you still face error in sending email, with the same error message. Try this:
$mail->SMTPSecure = 'tls';
$mail->Host = 'smtp.gmail.com';
just Before the line:
$send = $mail->Send();
or in other sense, before calling the Send() Function.
Tested and Working.
answered Jun 11, 2014 at 19:30
JackSparrowJackSparrow
9081 gold badge11 silver badges8 bronze badges
1
The other post is correct to resolve the issue but doesn’t address how to do it if the 2-step-verification is turned on. The option to allow the less secure apps is NOT available then. Here is an answer to how to do it:
a. Go to the URL of `https://myaccount.google.com/` and click `Sing-in and security`
b. Click on the app password.
You will reach a page like this,
c. Create name of your app and generate a password for the respective app.
d. Use that password acquired here inside the app.
This should resolve the issue.
answered May 20, 2018 at 10:16
ArefeArefe
10.4k16 gold badges101 silver badges159 bronze badges
0
I had the same issue and did all the tips including Gmail setting (e.g. less secure apps access) with no luck. But finally when I changed password to something different, for some reason it worked! FYI, the initial password did not have any special characters.
answered May 24, 2016 at 22:57
EhsanEhsan
1,02211 silver badges20 bronze badges
- first go to https://myaccount.google.com
- Select Security tab
- Scroll down and select ‘Less secure app access’
- Turn on access
This will solve my “SMTP Error: Could not authenticate” in PHPMailer error.
answered Apr 29, 2020 at 13:07
ruwanmadhusankaruwanmadhusanka
7812 gold badges7 silver badges15 bronze badges
I had the same issue and did all the tips with no luck. Finally when I changed password to something different, for some reason it worked! (the initial password or the new one did not have any special characters)
answered Aug 18, 2019 at 14:06
0
The correct answer:
Go to «Manage your google accounts => Security => Signing in to Google => App passwords».
Generate your maill account password there (that will be used from other device)
answered Apr 13, 2022 at 9:49
I had the same problem with authentication. The fix was to set up 2-step verification and create an application specific password for the device ( error messages for blocking the device will appear in your account settings->»Notifications and alerts» if you problem is the same with mine)
answered Jan 29, 2015 at 21:35
It was the selinux issue. I just updated the below given part in /etc/selinux/config file
SELINUX=permissive (it was SELINUX=enforcing before).
then just reboot the system by giving
reboot
Now the mail goes without any hassle.
Configuration
From Email Address : [noreply@yourdomain.com]
From Name : [your domain name]
SMTP Host : smtp.gmail.com
Type of Encryption : SSL
SMTP Port : 465
SMTP Authentication : YES
Username : [your mail id]
Password : [your password]
answered Feb 10, 2016 at 7:17
SMTP Error: could not authenticate
I had the same problem. The following troubleshooting steps helped me.
- I turned off two-factor authentication in my gmail account.
- I allowed less secure apps to access my gmail account. To get it working, I had to go to
myaccount.google.com->Sign-in & security->Apps with account access, and turnAllow less secure appstoON(near the bottom of the page). - At this step, when I tried to register a user, I would get the same error. Google would sent me a warning message that someone has my password and the login was blocked.
- Gmail will then provide you with options. You either click whether the activity was yours or not yours. Click the option that the activity was yours.
- Try registration again. It should now work.
cSteusloff
2,4376 gold badges27 silver badges50 bronze badges
answered Dec 14, 2017 at 11:47
There is no issue with your code.
Follow below two simple steps to send emails from phpmailer.
You have to disable 2-step verification setting for google account if you have enabled.
Turn ON allow access to less secure app.
answered Apr 12, 2018 at 7:24
PHPMailer is a great tool to send emails safely and easily using SMTP authentication.
But, sometimes this may fail due to incompatible server settings or incorrect SMTP configuration.
“smtp error: could not authenticate” is one such problem reported by website owners when using PHPmailer to send emails.
At Bobcares, we resolve such email errors as part of our Outsourced Technical Support for web hosting providers.
Today, let’s see the top 5 reasons for this error and how our engineers fix it.
What is this “smtp error: could not authenticate” error?
Simply put, this error says: “You try to connect to SMTP server, but it can’t authenticate you“.
So, it could mean,
- The PHP application was able to connect to SMTP server, but the authentication failed.
- Application was not able to connect to the SMTP server.
What’s wrong here? Let’s have a quick look.
Causes and Fixes for “smtp error: could not authenticate” error in phpmailer
1) Wrong SMTP authentication details
Each mail server uses an authentication system to validate users before they can connect and send emails.
When you send an email from your script, the mail server attempts to identify the user with the account’s username and password.
If this authentication fails, the mail server rejects the connection and users receive the error “smtp error: could not authenticate“.
Solution
We’ll ensure that correct username and password are given in the mail script.
In case of default email accounts, the full username(user@domain.com) should be given in the application.
Also, if the password was recently modified, it should be updated in the email application.
2) Wrong SMTP port and SMTP Host
Users should enter the mail server details in the “$mail->Host” field of the email application.
For example, if you use Gmail as your mail server, the hostname should be “smtp.gmail.com“.
Sometimes, a typo in the hostname or an inactive mail server result in this error.
Similarly, for port numbers, the default SMTP port is 25, but some mail servers use custom ports, such as 587, to avoid spam.
Also, some mail servers will be configured to allow emails only via SSL port 465.
It is also possible that some email providers restrict access to their SMTP port using firewall rules.
Incorrect port entry in SMTP settings or firewall restrictions may cause email delivery errors.
Solution
We’ll ensure the DNS connectivity of the mail server with the command.
dig mail.domain.com
Also, to identify the correct SMTP port and confirm connectivity to the SMTP port, we use the command:
telnet domain.com 25
We cross-check the SMTP settings in the application and make sure that correct SMTP host and port is used.
If we find any firewall restrictions, the IP should be whitelisted in the firewall.
3) SMTP encryption settings
For secure email transmission, most users prefer SMTP with encryption. SSL and TLS are the 2 encryption protocols used.
But, on some mail servers, SSL/TLS support may not be enabled or the existing SSL certificate may have expired.
What if users specify encryption in their application? Result is “smtp error: could not authenticate” error.
Solution
Our Support Engineers ensure that Apache and PHP are properly configured on the server with ‘mod_ssl‘ and ‘openssl‘ so that SSL can work on the server.
We’ll also verify the validity of mail server’s SSL certificate using the command:
openssl s_client -connect mail.example.com:25 -starttls smtp
So, the solution here is to properly configure SSL for the server or remove the encryption used in the SMTP settings.
4) Google blocks insecure access
Gmail enforces strict security restrictions.
If an app doesn’t meet these security standards, it may block access because these apps are easier to break into.
Users who authenticate to Gmail server receive the error “smtp error: could not authenticate” because Google considers username and password login as insecure.
Solution
Ideally, we reconfigure the app so that it meets the Google standards. If this is not possible, we’ll help website owners to loosen the security restrictions using the below steps.
- Sign in to the Google admin console.
- Go to Security > Basic settings.
- Go to Less Secure Apps.
- Turn on Allow less secure apps.
Allow less secure apps in gmail account
5) Expired Password
This can happen once in a while.
Some servers are set to auto expire passwords and app maintainers forget to update them in time.
When the application tries to connect, the mail server could not validate the password.
Result is “smtp error: could not authenticate” error.
Solution
This usually happens when the account owner missed the notification email about password expiry.
In such cases, we reset the password and also update it in the email application.
We also make sure that the notification email is set correctly, and in some cases, we remove the password expiration set for the mailbox.
Conclusion
“smtp error: could not authenticate” is a common error when users send emails via PHPMailer using SMTP authentication. This error occurs when the application can’t establish an SMTP connection to the mail server. Today, we’ve seen the top 5 causes of this error and how our Support Engineers fix them.
PREVENT YOUR SERVER FROM CRASHING!
Never again lose customers to poor server speed! Let us help you.
Our server experts will monitor & maintain your server 24/7 so that it remains lightning fast and secure.
SEE SERVER ADMIN PLANS
var google_conversion_label = «owonCMyG5nEQ0aD71QM»;
За последние 24 часа нас посетили 11532 программиста и 1149 роботов. Сейчас ищут 165 программистов …
-
VaneS
Активный пользователь- С нами с:
- 16 ноя 2011
- Сообщения:
- 631
- Симпатии:
- 3
- Адрес:
- Россия
Здравствуйте, у меня при отправке по SMTP выводится ошибка:
-
SMTP Error: Could not authenticate.
Как это исправить?
-
Команда форума
Модератор- С нами с:
- 15 мар 2007
- Сообщения:
- 9.901
- Симпатии:
- 968
правильно авторизоваться на smtp-сервере. русским по белому написано что? ошибка смтп: не смог аутентифицироваться
-
VaneS
Активный пользователь- С нами с:
- 16 ноя 2011
- Сообщения:
- 631
- Симпатии:
- 3
- Адрес:
- Россия
Почему с локального сервера все работает, а с удаленной VPS выдает эту ошибку? Ранее все работало, а на этой неделе просто перестал отправлять письма
-
Команда форума
Модератор- С нами с:
- 15 мар 2007
- Сообщения:
- 9.901
- Симпатии:
- 968
мб настройки смтп сменили?
-
VaneS
Активный пользователь- С нами с:
- 16 ноя 2011
- Сообщения:
- 631
- Симпатии:
- 3
- Адрес:
- Россия
Да в том и дело что ничего не меняли. Пытался подключаться к майлу и яндексу, ошибка оставалась прежняя, хотя ранее все работало нормально.
-
Предположение: у хостера обновили ssl, php-ssl — нет.
-
VaneS
Активный пользователь- С нами с:
- 16 ноя 2011
- Сообщения:
- 631
- Симпатии:
- 3
- Адрес:
- Россия
-
Попробуй поиграть с безопасностью транспорта:
$mail->SMTPSecure = ‘tls’;
или
$mail->SMTPSecure = ‘ssl’;Добавлено спустя 2 минуты 28 секунд:
я понимаю, но вы обновляли openSSL после небезызвестного бага?
-
Команда форума
Модератор- С нами с:
- 15 мар 2007
- Сообщения:
- 9.901
- Симпатии:
- 968
-
VaneS
Активный пользователь- С нами с:
- 16 ноя 2011
- Сообщения:
- 631
- Симпатии:
- 3
- Адрес:
- Россия
Кажется нет, а как это сделать?
Добавлено спустя 9 минут 53 секунды:
Моя CMS использует phpmailer, нашел там строку и заменил настройку, все заработало, спасибо большое!!!
Так все же, как обновить на сервере SSL? -
Команда форума
Модератор- С нами с:
- 15 мар 2007
- Сообщения:
- 9.901
- Симпатии:
- 968
руками из исходников скомпилировать. ну это если хорошо знаете что это. иначе дождитесь когда ментейнеры обновят rpm в репах центоса.
-
Там, чуть ли не в одних из первых появляется.
yum check-update
прочитает базу и выплюнет длинный список того, что давненько не обновлялось.
далее 2 пути:
1) обновить 1 openssl: yum update openssl
2) обновить все: yum update
That openssl command shows this:
CONNECTED(00000003)
depth=0 CN = becas
verify error:num=18:self signed certificate
verify return:1
depth=0 CN = becas
verify error:num=21:unable to verify the first certificate
So, first of all it’s a self-signed cert, which they really should not be using for a public service.
I extracted their certificate and info:
Certificate:
Data:
Version: 3 (0x2)
Serial Number:
10:cd:81:94:00:1a:a1:b4:4f:75:1f:7e:c8:9c:0d:3e
Signature Algorithm: sha1WithRSAEncryption
Issuer: CN=lecas
Validity
Not Before: Mar 3 18:34:11 2016 GMT
Not After : Mar 3 18:34:11 2021 GMT
Subject: CN=lecas
Subject Public Key Info:
Public Key Algorithm: rsaEncryption
Public-Key: (2048 bit)
Modulus:
00:b9:7c:a1:ad:4e:56:78:2b:28:19:68:18:68:8e:
...
Exponent: 65537 (0x10001)
X509v3 extensions:
X509v3 Key Usage: critical
Digital Signature, Key Encipherment
X509v3 Subject Alternative Name:
DNS:lecas, DNS:lecas.av.it.pt
X509v3 Extended Key Usage:
TLS Web Server Authentication
X509v3 Basic Constraints: critical
CA:FALSE
Signature Algorithm: sha1WithRSAEncryption
2f:d7:e1:d0:6f:7c:fc:5a:ea:be:25:a1:3d:ed:bb:aa:0a:10:
...
Weirdly, this says the name is lecas rather than becas — it may be that they rotate SMTP connections between multiple servers with different names. Either way it doesn’t match webmail, and self-signing isn’t helping. Overall this mail server is very badly configured. I think your only way through this is to disable encryption and tell it to use LOGIN auth:
$mail->SMTPDebug = 2;
$mail->isSMTP();
$mail->Host = 'webmail.av.it.pt';
$mail->SMTPAuth = true;
$mail->AuthType = 'LOGIN';
$mail->Username = 'username';
$mail->Password = 'password';
$mail->SMTPSecure = 'tls';
$mail->Port = 25;
$mail->SMTPOptions = array(
'ssl' => array(
'verify_peer' => false,
'verify_peer_name' => false,
'allow_self_signed' => true
)
);
Even though you’re suppressing all the verification here, it will at least encrypt your traffic. If it still fails to log in, then I think you need to take this up with your ISP, and ask them to fix their certificates while you’re at it.