How to check installed perl modules on a server

To check the installed perl modules on a cpanel server, you can use the command provided below.

[email protected] [~]# instmodsh
Available commands are:
   l            - List all installed modules
   m <module>   - Select a module
   q            - Quit the program
cmd? l
Installed modules are:

No response from subprocess (/usr/local/cpanel/whostmgr/docroot/cgi/addon_nginx.cgi) with exit signal: 2

While accessing Nginx Admin in WHM, you may receive the following error;

No response from subprocess (/usr/local/cpanel/whostmgr/docroot/cgi/addon_nginx.cgi) with exit signal: 2

To resolve the issue, you need to install the following perl module;

[email protected] [~]# /scripts/perlinstaller Task::Cpanel::Core

Once installation is completed, refresh the page, it should be working fine without any error.

How to set limit to remove the Frozen emails automatically?

To set auto-delete for the frozen emails, you need to edit the exim configuration file on your server.

# vi /etc/exim.conf

timeout_frozen_after = 5d ( 5 Days )

# /etc/init.d/exim restart

That’s it!

Web server software (WebServerX) is not supported, sorry.

After installing moodle by using Fantastico or softaculous, its showing the following error.

Web server software (WebServerX) is not supported, sorry.

This is because the mod_security installed on the server and it can be resolved by editing the mod_security configuration file.

# vi /usr/local/apache/conf/modsec2.conf

search for

SecServerSignature "WebServerX"

and comment it, save the file and restart the apache service.

Moodle should be working fine now. exceeded the max records and failures per > hour (5/5 (%)) allowed. Message discarded.

In cPanel 11.32, a new feature is added to limit the ability of exploited or hacked sites to send out spam emails. A few customers who send out mass mailings have been triggering this feature, due to the number of bad/undeliverable email addresses on their lists.

Due to this feature you may get the following bounce back.

“Domain has exceeded the max defers and failures per hour (5/5 (26%)) allowed. Message discarded.”

cPanel will regularly monitor the emails sent through all email accounts on your domain, and if, over the past hour, more than 25% of the attempted deliveries have failed, outbound email will temporarily be limited.

To solve the issue,remove following file.


and restart the exim service or you may need to disable the option “Ratelimit incoming connections with only failed recipients” in tweak Settings in WHM. If you still have an issue with this, in Tweak settings, change the value for “Maximum percentage of failed or deferred messages a domain may send per hour”. The option is used for the maximum percentage of a domain’s outgoing mail that can consist of failed or deferred messages. Once the domain exceeds this percentage, it is temporarily blocked from sending mail.

If you’re not sure exactly what is causing this, you can probably figure it out by using the Email Trace icon in your hosting control panel. When you click the Email Trace icon, you’ll see a field where you can enter a recipient’s email address and then click a “Run Report” button to get information about email sent to that recipient. If you enter nothing for the recipient email address, you’ll get back data for all email traffic, and as you look through it you should see groups of bounced messages which can help you determine what sender caused the problem, and why.

SoftException in Application.cpp:422: Mismatch between target UID (99) and UID (502) of file

Sometimes on a suphp enabled server, you may get internal server error for a website and in error log it shows the folowing error;

Premature end of script headers: index.php

SoftException in Application.cpp:422: Mismatch between target UID (99) and UID (502) of file “/home/xxxxxxxx/public_html/index.php

To resolve the issue, check the ownweship and permissions of the files and folders. On a SuPHP enabled server, the file permissions should be 644 whereas the folders should have 755 and the ownership sould be cpaneluser:cpaneluser

If you still have an issue after correcting the permissions and ownership, check the httpd.conf and check the user set for the domain name. If its set to nobody, change it to cpaneluser.

You are done!

Latest visitor logs not working in cpanel

Sometimes the latest visitors stats is not showing in the cpanel, to resolve the issue, you can use the following steps.

Try to change WHM \ Tweak Security \ “Delete each domain’s access logs after stats run” from ON to OFF.


It’s possible the the latest visitors cache is corrupted for this account. Try using the following command to move the existing cache out of the way so it can be regenerated:

# mv /home/username/.cpanel/nvdata/latest_visitors /home/username/.cpanel/nvdata/latest_visitors_old

Replace “username” with the username of the account.

Cphulk Protection

cPHulk is a small program developped by the cPanel team and is exclusive to cPanel / WHM control panels. It’s a brute force protection which looks for logins for PAM services. Based on the configuration, it will block an IP after a specified number of failed logins from a specific IP (or for a specific account) for a specific period of time. It covers the services like, courier,dovecot,exim,pure-tpd,cpaneld,webmaild,whostmgrd,sshd and cppop. In “cphulkd” database,there are separet tables for each service.

cPHulk stores failed login attempts in a database. This is useful for determining problem IP addresses that may need to be blocked from accessing your server altogether.

If you want to enable cPHulk protection in WHM, you will have to disable the “UseDNS” option in sshd_config.

To enable the cPHulk protection, Login to WHM,

Main >> Security Center >> cPHulk Brute Force Protection and enable/disable it there.

You can configure the settings there. One of the common mistakes when enabling cphulkd on your cpanel/whm is not to add your local ip to the whitelist first which locks you out of your own cpanel/whm. You can whitelist your own IP in White/Black List Management.

However, the database “cphulkd”, may need to be cleared from time to time. You can clear the database by clicking “Flush DB” option available in cPHulk Brute Force Protection menu in WHM or on CLI use following command,

# echo "delete from brutes; delete from logins;" | mysql cphulkd

Try to login now.

“cPanel & WHM Update Blocks” error on the main page of WHM when we login to WHM

This issue is caused due to expired cpanel license or the corrupted license file.

It can be resolved by moving /var/cpanel/update_blocks.config and resynchronizing the cPanel license with /usr/local/cpanel/cpkeyclt.

# mv /var/cpanel/update_blocks.config /var/cpanel/update_blocks.config.bk

# /usr/local/cpanel/cpkeyclt

If its still the same, try to disable the CSF firewall by

# csf -x

and then resynchronizing the cPanel license.

database error for horde and roundecube

Sometimes you may face the following errors in webmail.

horde : A fatal error has occurredDB Error: connect failed

roundcube: DATABASE ERROR: CONNECTION FAILED!Unable to connect to the database!

Most probably, its an issue with the databases associated with horde and roundcube, so please check related error logs by

# vi /var/cpanel/horde/log/horde_0.log

Press Shift+G and check the error at bottom.

Feb 27 03:16:06 HORDE [emergency] [horde] DB Error: connect failed:  [nativecode=Access denied for user ‘horde’@’localhost’ (using password: YES)] ** mysql(mysql)://horde:[email protected]+localhost:3306/horde?persistent=1&charset=utf-8&ssl=1&splitread= [pid 18142 on line 398 of “/usr/local/cpanel/base/horde/lib/Horde/Perms/sql.php”]

# vi /var/cpanel/roundcube/log/errors

Press Shift+G and check the error at bottom.

[27-Feb-2012 03:15:09 +0000]: DB Error: _doConnect: [Error message: Access denied for user ’roundcube’@’localhost’ (using password: YES)]
[Native code: 1045]
[Native message: Access denied for user ’roundcube’@’localhost’ (using password: YES)]
** mysql(mysql)://roundcube:[email protected]/roundcube in /usr/local/cpanel/base/3rdparty/roundcube/program/include/rcube_mdb2.php on line 102 (GET /cpsess7853727673/3rdparty/roundcube/index.php)

The issue can be resolved by forced update

# /usr/local/cpanel/bin/update-horde –force
# /usr/local/cpanel/bin/update-roundcube –force

Once update completed, check the webmail.

You are done!