3
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1answer
395 views

How did this email bypass my SPF settings?

I received a phishing email this morning that appeared to come from one of my addresses to itself. Looking at the headers, I found something interesting. DomainKey-Status: no signature ...
0
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1answer
200 views

Blocking External Mail Sent w/ Spoofed Email Address

We recently got an email from an outside server that had a spoofed "From:" header that was the email address of one of our users. Is there a way to have sendmail reject emails coming in from an ...
0
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2answers
289 views

My exchange 2003 mail server is blocked by RBL lists. Someone is sending spam from inform@mydomain.com

All outgoing email to external recipients from my Exchange 2003 server is getting blocked by RBL lists. I'm new to administrating Exchange and i checked the Message Tracking Center under System ...
1
vote
1answer
157 views

Preventing Email Spoofing

I use Google Apps with my domain. Recently, we have begun to receive spam that gets past Google's spam filters. They are from our own email addresses. I am wondering how to prevent this kind of ...
2
votes
2answers
2k views

Reject obviously spoofed messages in Exchange 2007 SP2

I have an Exchange 2007 SP2 server which happily accepts SMTP messages whose sender is SomeRandomString@mydomain.com and the recipient is SomeRealUser@mydomain.com; this leads to all sort of spoofing ...