I'm working on a Laravel 4.2 application that needs to be able to send emails. When the SwiftMailer component contacts the Microsoft Exchange server we use here it's receiving the following reply:
* OK The Microsoft Exchange IMAP4 service is ready.
* BYE Connection is closed. 13
My understanding is that I should be seeing SMTP response codes 220 and 221 instead of those asterisks; the SwiftMailer module is throwing an Exception when it receives the message without the codes.
I'm trying to do some investigation before bugging my coworker who manages the server in question. Does anybody have an idea how this substitution of asterisks for the codes may be occurring? I'm confident based on reviewing the code in SwiftMailer than this isn't occurring to the text of the response after it's received. Is this some sort of Exchange server security feature I'm unfamiliar with (and can't imagine the value of)?
The messages indicate that you are talking to an IMAP server, not an SMTP server. I'm guessing you put the wrong port number somewhere.
Odds are that you've got an "intelligent" network device between you and the server that's doing traffic inspection. I've seen this with Cisco devices, where the SMTP connection banner is replaced with a string of asterisks and all the command words in the SMTP traffic are replaced with "XXXX".
Related
My company has 4 different third party applications that use 4 different gmail addresses to send mail over port 587. One of the applications is distributed across over a hundred clients.
All four apps stopped working last week. I've been struggling to figure this out with GSuite support for the past week and they have so far been very unhelpful. One representative pointed to this recent update as the likely culprit:
https://gsuiteupdates.googleblog.com/2020/04/improve-email-security-in-gmail-with-TLS.html
But I don't have a ton of experience with mail servers and much of this is going over my head. I'm not sure why exactly the above update cause our apps to stop working.
The apps are failing to establish a TLS connection to the server and result in the following error:
handshake failure
Closing connection in response to fatal SSL/TLS alert.
Aborting handshake due to fatal alert
This comes after receiving a "Ready to start TLS" response from the smtp.gmail.com server.
All of the apps are using the Chilkat Mailman Active X component for the mail features.
https://www.chilkatsoft.com/refdoc/xChilkatMailManRef.html
Assuming the recent update is the actual culprit, I'm wondering if someone can explain why this caused our applications to stop working? Has GMail stopped supporting StartTLS? I also need to know if there is anything we can do from our GSuite account to get this working again without having to update over a hundred client applications.
The first support rep I spoke to suggested doing the following in the google admin console:
Apps -> G Suite -> Settings for GMail -> Advanced Settings -> Secure transport (TLS) compliance:
We unchecked the "Require CA-signed certificate" box and saved the setting. This has not resolved our problem.
The support rep also briefly mentioned the "Alternate Secure Route" setting in Gmail advanced settings, but I'm not sure if he knew what he was talking about or if this is applicable to our issue.
Edit
It looks like this is a combination of the GMail server update and some sort of incompatibility in the Chilkat mail component. I tried testing with a trial of a newer version of the component and SMTP works using the same settings with this component.
The developer of the component says he is not able to help me with this issue unfortunately. So I'm still wondering why the GMail server update caused the old component to stop playing nicely. I'm hoping that if I can understand what the specific change is, I can find a solution that doesn't require a major rollout.
My java mail client also just stopped working not long ago. I was using TLS connection as well. I got authentication errors.
I look forward to your findings!
-- I found my issue:
https://myaccount.google.com/u/1/lesssecureapps was no longer less security
I have a Coldfusion page (CF10) that creates a report and sends it via cfmail to a list of recipients. The ones in our internal domain are receiving, but the external addresses are not.
I found a couple threads where people were having the exact same problem, and the solution was to add the CF server's IP address to the Exchange server. So our IT guys did just that - they added the IP addresses of all of our production servers to the receive connector on the Exchange server. However, the mails are still not being relayed, and I'm continuing to get the same message in the mail log:
javax.mail.SendFailedException: Invalid Addresses; nested exception is: com.sun.mail.smtp.SMTPAddressFailedException: 550 5.7.1 Unable to relay
I'm not familiar with everything that needs to happen to make the Exchange Server relay email to external addresses. Adding the IP addresses to the receive connector obviously isn't enough. Are there other steps that need to be performed?
Coordinate with your IT guys. Write a ColdFusion page that they can run that sends mail to an external address they can access. Then tell them to do what they have to do to receive mail at that address.
Solution was simple - we originally specified the mail server in the cfadmin mail settings, but included no username/password. That worked fine, until we wanted to start sending cfmails to addresses outside of our own domain. So IT created a dedicated "Noreply" account for this purpose, and I entered the username/password in the cfadmin mail settings.
Following Problem: I have written a mailing-list via PHP, SwiftMailer and Postfix. On my Old server it worked without any problems, but Since I moved to another Server (Exactly same configuration, but other IP) the list-mails stuck in the Spamfilter of the Receivers. (Espacially in Google Mail)
Is there anything I have to do escept rerouting the URL DNS-Records, that Google sees, that "I am that Server" and the mail is no spam?
First, check that your outgoing mail server is identifying itself correctly in the HELO command (or EHLO command) when it connects to a receiving mail server. There should also be an A record for this name that should point to the IP address of the mail server. Also, this IP address should reverse to some name (possibly, but not necessarily, the same name as above), and this name should point to the mail server's IP. If any of this is not right, then most spam filters will not consider your server to be a 'real' mail server, and will most likely flag any message sent from your server as spam. This is how many spam filters block spam that originates from computers that have been taken over as 'zombies'.
Another thing to do is to check that you mail server IP is not on any blacklists. You can use MXToolbox for this: http://mxtoolbox.com/blacklists.aspx
Another thing you can do is use port25's verifier tool. This tool will spot any red flags that might be causing your messages to be flagged as spam. See http://www.port25.com/support/authentication-center/email-verification/ for more info.
Last but not least, you might want to setup an SPF record for the domain that you are sending these messages from, to indicate that the IP of your mail server is authorized to send mail from this domain. This will help a lot. For more info, see: www.openspf.org.
I would like like guidance regarding an issue we are having on our CentOS server.
Just recently we noticed that we cannot send emails to Hotmail.com mailboxes from our domain email. I also discovered that we're getting a lot of mail delivery failure emails in one of the inbox's that we don't use.
I've checked the mail logs and saw some suspicious activity. Unfortunately, I don't know much with regards to mail server and how they behave. Can someone shine some light on this situation and tell me if some is connecting to our SMTP server remotely and sending spam emails to various recipients? What other steps should I take to prevent this?
Here is part of the log:
2013-06-09 05:43:27 SMTP connection from [110.52.1.237]:13088 (TCP/IP connection count = 1)
2013-06-09 05:43:32 no host name found for IP address 110.52.1.237
2013-06-09 05:43:41 SMTP connection from [110.52.1.237]:13461 (TCP/IP connection count = 2)
2013-06-09 05:43:46 no host name found for IP address 110.52.1.237
2013-06-09 05:43:46 unexpected disconnection while reading SMTP command from (iem.net) [110.52.1.237]:13088
2013-06-09 05:43:55 H=(qbnngj.com) [110.52.1.237]:13461 sender verify fail for <wqnsjzyyc#qbnngj.com>: The mail server could not deliver mail to wqnsjzyyc#qbnngj.com. The account or domain may not exist, they may be blacklisted, or missing the proper dns entries.
2013-06-09 05:43:55 H=(qbnngj.com) [110.52.1.237]:13461 F=<wqnsjzyyc#qbnngj.com> rejected RCPT <support#greenXXXX.com>: Sender verify failed
2013-06-09 05:43:55 unexpected disconnection while reading SMTP command from (qbnngj.com) [110.52.1.237]:13461
As you can see above, the IP that connected to the SMTP server is from China. I have a dozen of similar connections made in the log.
I am not sure how to resolve this issue.
Any help would be appreciated.
Thank you,
Max
You have two separate problems.
Sending to Hotmail: They have a web page regarding their own private white list, and if you're not on the list, you get blocked.
Receiving delivery status notices for messages not sent: Someone is spoofing your domain in messages they're sending to others. You need to protect your domain with some authentication technology. The two most common are called "sender policy framework" and domainkeys.
I am using a PHP script for sending emails by IIS 5.1 SMTP.
The emails, go to outbound folder. really path is C:\Inetpub\mailroot\Queue.
after a seconds, it start to send emails properly, but after sending 5 or 6 emails, it stops to send the other ones. SMTP service is still start and it seems there is no problem to SMTP service.
but,If i restart the service, it sends 1 or 2 other emails and then, it stops again.
I mean sending emails stop but service is start.
by the way, emails are stucked in Queue folder.
Also i checked Badmail folder. it is empty
Thanks
are all the emails to the same network? I have seen behaviour like this when the recipient server bans you, yahoo's (xtra) used to do it sometimes to our server in particular. You can check the logs in event viewer for something from the smtp server, you'll find a message from the other server saying something to the effect that you have been temporarily banned, possibly with more detail about why. Trying to connect via telnet also gives you the same message.
When this happens windows will try and send them again later. Restarting the server starts to try sending again and if the ban condition has been lifted messages will flow for a while again until you are rebanned.