Hi I am using comcast server for email on Asp.net, I am facing issue while sending email, What is happening is when I am setting from-address of different email domain then its failing and throwing error :

Transaction failed. The server response was: 5.2.0 STOREDRV.Submission.Exception:SendAsDeniedException.MapiExceptionSendAsDenied; Failed to process message
due to a permanent exception with message Cannot submit message. 16.55847:301D0000, 17.43559:0000000094000000000000000200000000000000,
20.52176:140FCC841400101038020000, 20.50032:140FCC848417101044020000, 0.35180:02011330, 255.23226:5A020000, 255.27962:0A000000, 255.27962:0E000000,
255.31418:0201E165, 16.55847:9C000000, 17.43559:0000000068010000000000000100000000000000, 20.52176:140FCC84140010100B002900,
20.50032:140FCC848417101003003600, 0.35180:C9000000, 255.23226:0A004100, 255.27962:0A000000, 255.27962:32000000, 255.17082:DC040000, 0.27745:0A006400,
4.21921:DC040000, 255.27962:FA000000, 255.1494:E9000000, 0.37692:01000100, 0.37948:01000100, 5.33852:00000000534D545000000100, 4.56248:DC040000,
7.40748:010000000000010B01000100, 7.57132:000000000000000000000000, 1.63016:32000000, 4.39640:DC040000, 8.45434:BADA3CA85AC1194EB5D80A8D8905B0EB45004338, 5.10786:0000000031352E32302E313232382E3032303A435934...


If I setup Comcast Username as From-User then it works fine, How i can fix that? Please help

I am setting up a new HREL 7 server and trying to configure Postfix to send from one of the virtual IPs assigned to the server. I can successfully send mail, but the problem is that when mail is received, the header shows the server's primary IP instead of the virtual IP. It is flagged as spam due to a possibly forged header. The header includes:
Received: from mail.mydomain.com.com (unknown [21.31.41.51]

What am I missing?

Assumptions (not actual names/IPs):
Server's primary IP: 21.31.41.51
Server virtual IP = 61.71.81.91 (mail.mydomain.com.com)

DNS records:
mail.abc.com  A     61.71.81.91
mail.abc.com  TXT   v=spf1 ip4:61.71.81.91 ~all

/etc/hosts:
61.71.81.91 mail.abc.com

Postfix Configuration: (/etc/postfix/main.cf)
myhostname = mail.mydomain.com.com
mydomain = mydomain.com.com
mynetworks = 61.71.81.91/32
inet_protocols = ipv4
inet_interfaces = $myhostname, localhost

https://www.rackaid.com/blog/email-blacklists/

Refer to above link: it's said Barracuda has a list of bad IP : how can we download it?
I would also like to download for SpamHaus & CBL & any other if possible?

Hello,

I have a large outlook.pst file (8GB), that I imported into a IMAP account on our email server (hMailserver running on Windows Server). It looks like during the import some folders failed to import and now are missing on the email server.

Could you please advise is there any tool that I can use to compare the pst archive with the content of the IMAP account (probably the ost file in Outlook) ?

Dear Experts

We are using offfice 365 SMTP relay to send mails to the external users through the CRM application, i,e option 3 on the following URL
https://support.office.com/en-us/article/how-to-set-up-a-multifunction-device-or-application-to-send-email-using-office-365-69f58e99-c550-4274-ad18-c805d654b4c4 , this CRM system is allowed only to talk with <domain>.mail.protection.outlook.com on port 25 and 587 and rest of the access to the internet is blocked, not access for this CRM system to http/https to the external network.
1. we observed the CRM system workflow triggers the emails to the external network users only when the port 80 is opened for the CRM system at the gateway/firewall level,  we noticed the CRM system gets connected to internet and connects to crl.globalsign.com  and from here it is connecting to office365 smtp and emails are delivered.
2. when we disable access to external network i,e port 80 http blocked for CRM system at gateway/firewall then emails does not flow no packets flow found hence no mails are sent.
3. When only allowed CRM system can talk to crl.globalsign.com  then emails are getting triggered.
can you please help me understand how this office365 is working when it is configured to the CRM system. is it essential that CRM system to be allowed to talk to crl.globalsign.com . please suggest.

My customer had been getting a few phishing emails, which I could explain as opportunistic. He's the accountant in the school and the sender was supposedly the school director looking for money to be transferred to an account. The reply-to address was somewhere in Poland.  The school's web site has contact details for the school director and accountant so not too hard to  see how a phishing email could be constructed.

It took a bit of a turn when he got a second phishing mail with similar request to transfer money from the same source to a bank account in Spain.  This time though the phishing email was a reply to a legitimate email the accountant had sent to someone with a  sensitive attachment in it. Needless to say, he's concerned how his emails have been compromised and I'm struggling to come up with an explanation.

Their email server is an Exchange 2016 box, fully patched. They have a Sonciwall on the perimeter with OWA allowed access and IMAP and POP3 denied.

Anyone have any idea or explanation how the phisher has access to his emails and attachments??

Thanks
Enda

hi guys

We've had an email that looks like it has come from a bank claiming that one of their customers have had a fraudulent transaction on their card from one of our stores. I'm almost certain it is a phishing email of some sort.

I wanted to verify with you guys whether it is likely that the email address has been spoofed.

I won't be able paste the email address it is coming from. But as it claims to be from a bank, the sending server was the following:

Connection  Accepted
Sending Server
40.107.10.89 (mail-eopbgr100089.outbound.protection.outlook.com)
Sending Server HELO
gbr01-lo2-obe.outbound.protection.outlook.com
Connection Started
28 Sep 2018 5:45:45 PM GMT+01
Connection Finished
28 Sep 2018 5:45:45 PM GMT+01

Am I right to assume that any 'Bank' that is using Outlook as its sending server is using spoofing tactics?

Thanks
Yashy

I am about to build a separate, stand alone CentOS 7 server to just run postfix.  I work for a fairly large company that has 3 email domains, for ease lets call them 1.com, 2.com and 3.com.

1.com and 2.com will be having that email redirected to mimecast (www.mimecast.com), however 3.com needs to have the email sent to a different location (an internal Exchange server).  The reason for this is that 3.com will, in a few months be moving to Office365.

My question is, whats the best way in postfix to say "if 1.com or 2.com send ->  relay it via mimecast, and for 3.com send it another destination.

I have worked with postfix quite a bit, however mainly using basic configs, or basic mail relay for one single domain.

Thanks for your time,
Stu

Currently using O365 and wanted to know if there are any commands that could list all mailboxes that utilizes a Safe Senders List as well as to list the contents of their Safe Senders List.