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Questions tagged [email-server]

Refers to the hardware or software that make up a server dedicated to sending and receiving emails. Many popular modern email servers bundle other functionality for contacts and calendaring along email delivery.

Refers to the hardware or software that make up a server dedicated to sending and receiving emails. Many popular modern email servers bundle other functionality for contacts and calendaring along email delivery.

A list of mail servers can be found on Wikipedia, though sendmail, Microsoft Exchange Server, Postfix, and Exim are the most popular email servers, which together control over 85% of market share for SMTP service.

3157 questions
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What ports to open for mail server?

I have just finished setting up a Postfix mail server on a linux (ubuntu) platform. I have it sending and receiving email and it is not an open relay. It also supports secure smtp and imap. Now this is a pretty beginner question but should I be…
radman
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Why can't MX records point to an IP address?

I understand you should not point a MX record at an IP address directly, but should instead point it to an A record, which, in turns, points to the IP address of your mail server. But, in principle, why is this required?
dayuloli
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Do SPF Records For Primary Domain apply to subdomains?

I have a quick question regarding SPF records: Do they need to be present for all subdomains? Lets say that I have a TXT record with SPF info for domain.com Let's also say that I have a seperate email domain for subdomain.domain.com Will the SPF…
Mike B
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Is Postfix the same thing as Sendmail?

I have Postfix setup on my server so that I can send outgoing mail using the command-line: mail -s "Subject" address@example.com Is this using Sendmail or Postfix ? Is "Sendmail" just a software category or a distinct program ? If something is…
Xeoncross
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Is greylisting still an efficient method for preventing spam?

I've used greylisting on my servers for many years, but I don't know how effective it is nowadays. Is it still good for fighting spam in 2012? Or is the typical spammer MTA capable of resending greylisted emails now?
neu242
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How can I see the contents of the mail whose ID I get from postfix's mailq command?

I used mailq command and I got a line like for example: A705238B4C 603953 Wed May 23 11:09:58 apache@myserver.com So, now I'm wondering is there a way where I can "read" an actual content of the mail by its id A705238B4C
Nikola
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Postfix: Recipient address rejected: User unknown in local recipient table

When I try to send an email on my postfix server to an address on the same domain (for example, if the server hostname is mail.example.com and I try to send an email to test@example.com), I get the following error in the log and the email is not…
Tai Squared
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"My unqualified host name (foo.bar) unknown" Problem

When trying to start sendmail or send a mail using a wordpress plugin, this error shows up in the maillog: "My unqualified host name (foo.bar) unknown; sleeping for retry" After Googling the best advice was, "add foo.bar to the /etc/hosts file",…
Richard Stelling
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7 answers

Is it becoming impossible to be a small mail provider?

I operate a small mail server for my private emails, some friends who have websites and two NGOs. In total my server sends between 60 and 400 messages a day. Now a lot of these emails are personal mails, between two or more people who know each…
Stefan Seidel
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Why Does hotmail still reject my emails?

I have a very strange problem with my emails being marked as spam by hotmail. I just have configured Postfix + Dovecot on my server and all works perfectly. I can Send/Receive emails. I only have problems with hotmail accounts, I do not understand…
Dail
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Can postfix be set up to forward mail to multiple recipients

I have the following postfix virtual file: test@domain.com bob@me.com This correctly forwards all emails to test@domain.com to bob@me.com However I would like to forward these emails to bob2@me.com as well. I tried this change and it does not seem…
Sam Saffron
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34
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2 answers

Sending malicious email as a test

I have set up a working SMTP relay together with MailScanner. This SMTP relay is not — and will not be — able to relay email from the outside, only local email. Is it possible to send a malicious email with the terminal? I have googled around but…
Orphans
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How should I test Clam Anti-Virus?

I have setup a new email server and now I need to test that Clam Antivirus is scanning messages correctly. How should I do this in a safe and controlled way?
karthick
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33
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8 answers

Good idea? Refuse incoming emails with our own domain ending? (because they must be fake)

I have a question about our Exchange Server: Do you think it is a good idea to refuse incoming external e-mails that have our own domain in the ending? Like external eMail from fake@example.com? Because if it would be from a real sender in our…
Steffen Maier
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Which IMAP flags are reliably supported across most mail servers?

I am writing an application which reacts to emails sent to a mailbox. It retrieves the emails via IMAP. It will be deployed to a number of systems where I do not control the mail server configuration. I would like to use IMAP flags to indicate which…
Ben Butler-Cole
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