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eMail server security Blogs


How to setup Fail2ban to avoid Postfix SASL attack ?

Email spamming can ruin the IP reputation of any server!

But, what can we do to defend against spammers ?

Here, the solution is to block common spamming methods like brute-force password attacks, dictionary attacks, etc.

Fail2ban is a commonly used tool to block brute-force attacks in mail servers like Postfix.

But, configuration errors can cause Fail2ban to let through malicious connections.

That’s why, we help server owners to properly setup Fail2ban as part of our Dedicated Support Services for Web Hosts.

Today, we’ll see how to setup Fail2ban Postfix SASL configuration and the common failure points.

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Squirrelmail vs RoundCube vs Horde – The best of the lot!

Webmail is a great way to access your emails when you are away from your home.

And servers offer many options like SquirrelMail, RoundCube, Horde Mail etc. to access webmail.

All these options have many merits and some demerits. The right choice is often confusing to users.

At Bobcares, we help customer to effectively choose and set up these mail applications as part of our Dedicated Support Services for Web Hosts.

Today, we’ll do a comparative study of SquirrelMail vs RoundCube vs Horde Mail.

 

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Instant fix for Exim4 ‘mailing to remote domains not supported’ error

A message that you sent could not be delivered to one or more of its recipients. This is a permanent error. The following address(es) failed: user@domain.com . Mailing to remote domains not supported.

 

This is a commonly noticed error in new servers or servers with newly installed mail server such as Exim4, when sending mails to external mail addresses.

In our experience providing Technical Support Services for web hosting companies, we come across many sorts of email errors, and resolve them for our customers.

Today, we’ll see what causes the error ‘mailing to remote domains not supported’ and how we fix it in Exim4 servers.

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How to setup SMTP authentication in Exim4 mail server?

Most ISPs enforce SMTP authentication to send emails which helps them reduce spam.

But, this is not supported by most Linux distributions(Centos, Debian, etc.) by default.

So, you must manually configure your mail server to enable SMTP authentication, which requires many edits in the core configuration files.

In our role as Outsourced Tech Support, we help our web hosts and their Dedicated and VPS customers setup SMTP authentication in their servers.

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“550 SPF check failed” – Here’s how to fix

Email errors are frustrating especially when you do not know the exact failure reason.

For example, bounce messages like “550 spf check failed” often confuse email users whether the error is at sender side or recipient side.

At Bobcares, we help website owners to solve complex email errors as part of our Outsourced Technical Support services for Web Hosts.

Today, we’ll see the top causes for “550 spf check failed” error and how we fix them.

 

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“The server rejected one or more recipient addresses”- Here’s how to fix

Help please! When I send an email inside my domain it works fine… but once I send an email outside of the domain, I get the error: “The server rejected one or more recipient addresses. The server response was: 550 5.7.1 Unable to relay.”

That was a recent request that we received at our Outsourced Technical Support services helpdesk for Web Hosting providers.

Mail servers typically allows all genuine mails. But, if the sender email address appears as fraud, they simply reject mails.

Today, we’ll see what causes this mail error and how our Support Engineers fix it.

 

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“Destination smtp server rejected the sender” – Here’s how to fix it

Email errors are quite frustrating especially when you do not know why it is happening!

Though the bounce mail show some error text, that will just serve as a pointer to the possible reasons for the error.

One such error is “Destination smtp server rejected the sender” shown in email marketing programs like SendBlaster.

At Bobcares, we resolve many email related errors as part of our Outsourced Technical Support services for Web hosts.

Today, we’ll see the top reasons for this error and how we fix it.

 

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Migrating emails to Plesk – Here’s how to do it

Migrating the entire domain is pretty easy with Plesk Migration tool.

At times, when customer changes only their email provider, there is a need to migrate only email contents.

Doing this selective migration may not be easy and often end up in broken email accounts.

At Bobcares, we help website owners to do selective migration as part of our Dedicated Support Services for Web Hosting providers.

Today, we’ll discuss the steps involved in migrating emails under the domain to a Plesk server.

 

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ClamAV Directadmin Integration – Here’s how to do it

All Web Hosts need a mechanism to defend malware and virus attacks on their servers.

One of the popular choices is ClamAV. It is a free antivirus tool that helps to scan emails on DirectAdmin servers.

But, the downside is that, it works mainly via command line. So, the installation and maintenance may appear complicated to any average user.

At Bobcares, we help server owners to easily install and maintain ClamAV on their servers as part of our Dedicated Support Services.

Today let us discuss on how we install and set up ClamAV on DirectAdmin server.

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