Webmail error:Warning: main(../config/config.php): failed to open stream in cPanel

I got the following error in webmail

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Warning: main(../config/config.php): failed to open stream: No such file or directory in /usr/local/cpanel/base/3rdparty/squirrelmail/functions/global.php on line 18
Fatal error: main(): Failed opening required ‘../config/config.php’ (include_path=’/usr/local/cpanel/3rdparty/lib/php/:.’) in /usr/local/cpanel/base/3rdparty/squirrelmail/functions/global.php on line 18
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To Fix this issue, type the following command:-

# /scripts/fixwebmail

After running /scripts/fixwebmail you may get error like this:-

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chown: failed to get attributes of `/usr/local/etc/cpanel/base/webmail/data’: No such file or directory
chmod: failed to get attributes of `/usr/local/etc/cpanel/base/webmail/data’: No such file or directory
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For fixing this just issue the following command:-

# cp -p /usr/local/cpanel/base/3rdparty/squirrelmail/config/config_default.php /usr/local/cpanel/base/3rdparty/squirrelmail/config/config.php

Internal Server Error in webmail

You may get the following error in webmail:-

Internal Server Error
User ‘<username>’ is over quota.

Fix:-

Check the  disk quota of the user and the quota for the problematic e-mail account. If the quota is not exceeded then check the quota values in the file:-

# cat /home/<Username>/etc/<domain.com>/quota

jack:104857600
tom:10485760

Try to change the quota value.