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The domain already exists in the Apache configuration : Causes and Fix

Billing automation tools like “WHMCS” help Web Hosts to create and edit accounts in a jiffy.

But things like high server load, database connection errors etc. can cause WHMCS to fail which results in partial creation or removal of domains.

And such partial entries on the server can cause domain recreation to fail with the error :

“The domain “” already exists in the Apache configuration.”

As part of our Dedicated Support Services, we often see this error when customers try to migrate domains, or change domain as main account etc.

Today let us discuss 3 scenarios where this error pops up and how we fix them.


What causes the error “The domain already exists in the apache configuration.”?

On new domain creation, cPanel first checks if the domain name is already present in any of the server configuration files.

And if a match is found, it aborts domain creation with the error “The domain already exists in the apache configuration.”

We’ll now see the common reasons for cPanel to show “Domain already exists” error.


1. Addon Domain Creation

Addon domain creation or deletion from cPanel works correctly in most cases.

But when there are server issues like bad disk, high load etc., domain deletion process can get stuck half-way.  And then, addon domain entries are not properly removed from the server files.

When a customer tries to add the same domain again, it will result in the error shown in the image below:



But the domain never shows up under Addon Domains in cPanel.

The same error can happen even with domain migration or backup-restore as well.


2. Add new domain that matches server hostname

By default, cPanel adds an entry for server name in the Apache configuration file.

Some VPS server owners set the server name as their domain name itself. In such servers, when customers try to create a domain that matches server name, it shows the error “Domain already exists in the Apache configuration”.

It is important to ensure that server name is set as something like and not Then there will not be any issues while creating new domain


3. WHMCS Module Command error

WHMCS can malfunction when there are connectivity issues with server and this causes tasks to fail.

Due to such issues, if a webhosting provider re-submits the ‘create account’ button,  it results in the error :

Module Command Error:

The domain “” already exists in the Apache configuration.


How to fix “Domain already exists in the apache configuration”

Although there are many situations where this error pops up, the fix is to correct the duplicate entries for the domain.

Our Hosting Support Engineers check the server and remove entries for conflicting domain in Apache configuration file, httpd.conf. Then we rebuild Apache on the server.

But we’ve seen situations where error still exists due to domain entries present in cPanel user data files.

In such cases, we remove the user related files from /var/cpanel/userdata/ and clear user related cache. That fixes the error and domain creation works fine.


The presence of duplicate records for the domain in the Web server files results in account creation errors. We’ve discussed couple of scenario where server complains “Domain already exists” and how our Dedicated Support Engineers fix them.


“My IP is blacklisted. How to remove it?” – Experts answer

Help! My IP is blacklisted. All my mails are bouncing. How to remove it?

This is a common support request we resolve here at our Server Administration Services support desk.

Website owners wake up one day to find all their business mails bouncing, citing the reason that the server is a source of spam. (more…)

MySQL “stop: Unknown instance:” error – Why it happens and how to fix

Server errors are no fun.

And it is especially frustrating when the error is cryptic, like “Unknown instance“.

What does it mean, really?

A common error people face in VPS, Cloud and Dedicated servers is MySQL failing with “stop: Unknown instance:(more…)

Errors with cPanel Remote Mail Exchanger? Here’s how to fix them

Up until a few years ago, domains had both mails and websites set up on the same server.

Things have changed nowadays and many people use custom mail servers like Google, Outlook etc. to handle mails for their domains.

To make this happen, server management tools like cPanel provide a setting called “Remote Mail Exchanger”.

But setting up “Remote Mail Exchanger” is not intuitive to many website owners, and they often face mail bounces or mail errors due to misconfiguration of this setting.

As part of our Outsourced Technical Support for web hosts, we routinely resolve such email errors.

Today let’s go through the top two issues we’ve seen while setting up a Remote Mail Exchanger.


How things go wrong with cPanel Remote Mail Exchanger

In cPanel servers, there is an option called “Email routing” which decides how mail is handled for a domain.

By default, new accounts created on the server have mails handled by the same server.

But when the domain need to use another server for mail, the email routing has to be set as “Remote Mail Exchanger”.

Here’s how Email Routing is set for a domain in cPanel servers.

cPanel Remote Mail Exchanger - Email Routing


Mail server tries to send mails to another server after checking the Remote Mail Exchanger setting for the domain.

Listed below are the situations where mails fail due to this setting.


1. Remote Mail Exchanger not set

To enable external mail servers for a domain, website owners simply  set the custom mail servers (MX) records for the domain.

Unfortunately, that is not enough for mails to show up in the external mail servers.

Mails from website forms or other domains hosted on the same server still fail. This happens as the mail server tries to deliver the mails within the server.

To fix the problem, our Dedicated Support Engineers set the correct email routing as per the MX records of the domain.

Also we ensure that the correct values are present in the mail server configuration files like /etc/localdomains and /etc/remote domains as well.


2.  Incorrect value for Remote Mail Exchanger

Cpanel maintains two domain lists :

  • Domains whose mails are on the same server
  • Domains whose mails are on remote server.

When we change email routing for a domain, cPanel automatically adjusts these lists.

For example, when we set Remote Mail Exchanger for a domain, cPanel removes domain from local domains list and automatically adds to remote domains list.

But this may not work always due to bad server settings.

And when a customer wants to change their domain’s MX  to a different provider, say Google, he will set MX in dns records and change email routing to “Remote Mail Exchanger”.  Normally, this is enough for mails to show up at Google.

But if for some reason cPanel fails to remove this domain from the local domains list, mail server will still try to deliver all mails from other domains on the same server locally. This will result in email error “Recipient Not Found” as the original recipient exists at Google.

In such cases, for mail to work properly, our Dedicated Support Engineers do the following :

  1. Set mail routing to “Remote Mail Exchanger”
  2. Remove entries for the domain from the list of local domains
  3. Add the domain to the list of remote domains


Wrong setting of the cPanel Remote Mail Exchanger can cause mail issues for the domain. We’ve discussed two causes our Dedicated Hosting Engineers often see in the servers that we manage and how we fix them.


cPanel DNS cluster – The Pros and the Cons!

A slow website can harm your business as much as a broken site – And you wouldn’t want either of these to happen to you!

That’s where clusters and High Availability setup helps.

As part of our Dedicated Support Services, we configure and maintain High availability clusters for our customers who are web hosts.

A commonly configured one is the cPanel DNS cluster.


What is “Optimize Website” in cPanel? Is it enough?

Websites that load in 2 seconds are the new norm in SEO.

Google’s website auditor marks 1.2 seconds [1] as the ideal speed score, and it won’t be long before all business sites fall in line.

That brings us to the question : How do you improve your site speed? (more…)

How to fix “550-previous (cached) callout verification failure” email error

Spammers have made life difficult for us all.

These days even legitimate mails get snagged in the vast array of anti-spam defenses deployed by companies.

One such commonly misclassified anti-spam bounce is:
SMTP error from remote mail server after RCPT TO:<>:
host [x.x.x.x]: 550-Verification failed for <>
550-Previous (cached) callout verification failure
550 Sender verify failed


PHP mail function not working in cPanel – Causes and Fixes

PHP applications like WordPress, Joomla etc. send mail using a PHP feature (aka function) called “mail()”.

Hackers largely exploit the PHP mail function for spamming.

No wonder, Webhosting companies disable PHP mail function on the server as a rule of thumb.

This causes mail from applications like wordpress to fail with the following error.

"The e-mail could not be sent. Possible reason: your host may have disabled the mail() function."


Website owners still need a way to send mails from their websites. At Bobcares, we provide solutions for server owners  as part of our Outsourced Hosting Support services.

Today, let us discuss two reasons for php mail failure and how we fix them.


What causes php mail function to fail?

When you use PHP mail function, mails are sent directly from the webserver identity aka “nobody” user.

Since all web requests originate from same “nobody” identity, tracking down the real spamming website in a server becomes difficult.

So Hosting companies defend PHP mail () function abuse in two ways:


1. Prevent “nobody” user from sending mail

As a known source of spam, most Web-hosting servers prevent all mails from “nobody” identity.

For example, in a cpanel server, there is an option to turn OFF mails from nobody as shown in image below.

PHP mail function not working cPanel


But this action will block mails from legit users too, unless there are remedial features on the server.

So, our Dedicated Hosting Engineers enable special php modules like suphp, fastcgi, etc., which use website’s own identity to send mail.

This helps us to configure the mail server to limit the number of mails sent from each website.


2. Mail function present in disable_functions list of php.

Hackers can make use of certain php functions like “shell_exec”, “system” etc. to attack a server.

So Web-hosting companies disable such dangerous php functions on the server.

When PHP mail () function is also added in the disable_functions list, even mails from legit users are blocked.

In such servers, we help website owners configure their sites to send mail through the SMTP port instead of the PHP mail() function.

For this, we set up plugins and modules for websites such as “WP Mail SMTP” for wordpress, PHPMailer for Drupal etc.

In this way, all mails from the websites bypass PHP mail function, and are sent through the SMTP port of the mail server (like how mail clients like Outlook do).



PHP mail () function failure normally happens due to restrictions in the Web-hosting server. Here we’ve discussed two causes our Dedicated Hosting Engineers have seen and how we fix it.

Tired of Drupal admin access denied error? Here’s how to fix it

For as long as Drupal has existed, users have seen this error one time or the other:

Access denied

You are not authorized to access this page.

It might have appeared after a site migration, a server update or for no reason at all.

Drupal admins won’t be able to login to the admin panel, and no amount of cache clearing, or browser restarts would solve the issue.


2 causes for “550 REJECTED – Bad HELO – Host impersonating [DOMAIN]” & how to fix it

Mail errors. They hit you at your most vulnerable, and make you want to smash your laptop.

We know. Because we help website owners resolve email errors and other technical issues as part of our Outsourced Hosting Support services for web hosting providers.

Hosting users frustrated with cryptic email errors would submit a support request, and we’ll fix it for them in a few minutes.

Here’s an email bounce error we fixed recently in a Linux cPanel/WHM server: (more…)