smtp - phpmailer / IsSMTP causes 500 error but sends the mail 1 minute later

whenever $mail->isSMTP(); is set in phpmailer it "hangs" for about 1 minute, then it redirects to a:500 Service Unavailable page with XID: 2060448470.BUT one minute later i GET the mail that was sent. in the mail i can read:Received-SPF: pass ( domain of designates 2a00:16d8:0:4::200 as permitted sender) When i remove "$mail->isSMTP();" the email get sent right away BUT they dont get SPI = pass:spf=none ( does not designate permitted sender hosts).I really need SMTP to work ...Read more

phpmailer - Gmail SMTP debug: error "please log in via your web browser"

I'm having problems with gmail smtp server. I already read many posts here in StackOverflow about that subject.The best post I found about test the connection is this one.Although it is very well explained the error I'm getting I couldn't find a answer:Google SMTP just says "Please log in via your web browser and then try again". I'm completely sure that the password and the email (both in base64) are well encoded.As you can see here, in this image:,there is just one difference I can notice: the and password is sent in two steps....Read more

smtp - How to prevent RFC5322.From header spoofing

I have an email service in domain How can I protect it from spoofing USER email addresses in From header? Scenario: Attacker sends email from - connect to my SMTP service, authenticate correctly as malory and sends message with header From: alice@example.comSPF can't help, because attacker use my legitimate SMTP service, have own account and correctly authenticate.DKIM can't help either, from the same reasons - attacker uses real, legitimate email account, so massage have proper digital signatures.DMARC can't he...Read more

smtp - Catching a Email Loop from a out of office agent

Our Current email2fax gateway does not handle bounced emails very well. When a email is sent to the gateway the content is faxed out and a notification is sent to the original sender of the message.Problems happen when the original user turns on a out of office agent and messages will bounces between the 2 email gateways.I have tried to set in the outbound notification the following headersFromReply-ToBut as this is a proprietary gateway it does not allow me to set a custom Return-PATHsome silly mail servers send replies back to that.Are there ...Read more

Reverse DNS and SMTP

I'm in the middle of implementing Forward Confirmed Reverse DNS for my SMTP server. After reading around a bit, I found that it is best to do the lookup on the IP found at the other end of the SMTP connection (not in the mail header, because that IP is spoofed more easily). Once I have the hostname, I can compare it to the 'from' email domain in the header and determine if the email is valid. However, I was thinking about it further and realized that this might not be the IP I want to do a lookup against. If the email message had to travel thro...Read more

Using SMTP to Office 365 from Google Cloud Engine

I just hit a major block in a planned migration from Azure to GCP/GCE. GCP does not allow egress of SMTP on port 587. I double checked and their support confirmed this. The upshot is that I can't use the SMTP server in Office 365 from my GCEs as the requirement for SMTP when using O365 is port 587 at Bizarrely, (and somewhat contradicting the supposed reason for this block) port 2525 is open for SMTP traffic. Oh, and of course port 587 is open if you use Google for email!!Has anyone found a way around this, perhaps by gettin...Read more

amazon web services - Could not connect to SMTP host:, port: 465, response: -1

I am trying to send email with Amazon's SES/SMTP and I am getting the following error:javax.mail.MessagingException: Could not connect to SMTP host:, port: 465, response: -1Here is how I am trying to send the mail:Spring mail sender config:<bean id="mailSender" class="org.springframework.mail.javamail.JavaMailSenderImpl"> <property name="host" value="${mail.server}"/> <property name="port" value="${mail.port}"/> <property name="username" value="${aws.mail.smtp.user}"/&...Read more

smtp - How to properly set up DNS SPF records?

I'm sending weekly emails to subscribers and it turns out that messages are frequently going to the spam folder for users.I'm utilizing Amazon SES to send these messages and have added an SPF record according to their instructions: querying the SPF records for my domain I get the following back from record lookup and validation for: mydomain.tldSPF records are primarily published in DNS as TXT records.The TXT ...Read more

amazon ses - All my Aamzon SES SMTP ports are blocked

Today, I found out all my SMTP ports in Amazon SES are not open.Port 25 not opened on your server errornum: 110 : Connection timed outPort 2525 not opened on your server errornum: 110 : Connection timed outPort 587 not opened on your server errornum: 110 : Connection timed outPort 465 not opened on your server errornum: 110 : Connection timed outI failed to understand what's going on. Can anybody shed some light as to what needs to be done> This is a live server and all the new registrations are not getting emails...Read more

smtp - sending email continously using phpmailer and aws ses

I was using phpmailer to send emails from our ubuntu 14.04 server and we are using AWS SES to send emails with phpmailer. We are getting first two emails quickly but after that browser goes into a loop and didn't send emails for at least 2-3 minutes.I need it so that phpmailer send mails continuously without going into a loop....Read more - Need a lightweight, free, windows SMTP server

Anyone have any experience with 3rd party SMTP server for windows (server 2003)? I would like to set one up so that the cruise control can send reports of nightly builds and SVN check-ins.I would like the server to be lightweight and free (this will only be used for sending email) I know windows server 2003 has a SMTP server built in, but this machine is a virtual machine and I can't give it access to an install CD....Read more

smtp - How to check if server is sending out spam?

I checked my IP address today because I was getting bounced back emails and I see it has been blacklisted on a few lists. I only use my website to send out customer emails and no newsletter emails; so I don't send many emails out.I don't know why my dedicated IP address would be blacklisted; is there a way to check my server running Plesk to see if someone is using my IP address to spam?Thank you!...Read more

Unable to send mail through Google SMTP with PHPMailer

I'm trying to send out mail using Google's SMTP in combination with PHPMailer, but I can't get it to work. This is my code:$mail->IsSMTP();$mail->Host = "";$mail->SMTPAuth = true;$mail->SMTPSecure = "ssl";$mail->Username = "";$mail->Password = "**********";$mail->Port = "465";First I do not fully understand what should be filled in as 'SMTPSecure', some say 'ssl', other say 'tls'. Next for 'Port' I could enter '465' or '587'. But none of the combinations work... Note that I'm using a regular G...Read more