On brand new Plesk 8.2.x installations or on servers that have been upgraded to Plesk 8.2.x, you might run into this error when you attempt to log into squirrelmail after it was installed via RPM:
Error opening /var/lib/squirrelmail/prefs/default_pref
Could not create initial preference file!
/var/lib/squirrelmail/prefs/ should be writable by user apache
Please contact your system administrator and report this error.
No matter what you do to the /var/lib/squirrelmail/prefs/default_pref file, even if you chmod 777 the file, you will still get the error. If you check the /etc/php.ini, you will normally find safe_mode set to on.
;
; Safe Mode
;
safe_mode = Off
Simply change safe_mode to off and reload Apache. If you try to log into squirrelmail again, it should complete successfully. I've tested this on Red Hat Enterprise Linux 4:
# rpm -q squirrelmail
squirrelmail-1.4.8-4.0.1.el4
Better to set safe_mode just for Squirrelmail.
You can add this anywhere, but I like to set it in /etc/httpd/conf.d/squirrelmail.conf:
<Directory /var/www/squirrelmail>
php_admin_value safe_mode off
</Directory>
Stumbled into other problems with squirrelmail after solving this:
ERROR: Could not complete request.
Query: CREATE "Sent"
Reason Given: Invalid mailbox name.
Solved by editing /etc/squirrelmail/config.php
editing these lines:
$optional_delimiter = 'detect';
$default_folder_prefix = 'INBOX.'; <-- point at end
$trash_folder = 'INBOX.Trash';
$sent_folder = 'INBOX.Sent';