Making any kind of change to the back end of a modern content management system is always fraught with danger, so the question is – how to get to the bottom of the problem?

Unfortunately a lot of CMSs now use htaccess files to create clean urls and redirect to the correct location – so the problem may not be where you think at all!

The Logs
The best place to start any investigations are always the standard error logs. Normally, at /var/log/httpd/error.log but this can change based on your system configuration. To check the location of your error log simply check the apache.conf file. If there isn’t an error log listed in the virtual host for the domain then it will use the main one. Simply search the conf file for the word error (there will be a lot but you will get there).

Once you have this you can see what the error is with

tail -f log location

Hit enter a couple of times to create some white space in the log and then refresh your browser window. Now, hopefully, you have an error message!

Permissions error
The simple option …
Check your file and folder permissions and ownerships then change them as necessary.

File doesn’t exist
Check that it does …
With some CMSs the file may not exist so you need to look at the htaccess to see how the redirects work. Failing that you may need to check the admin panel/database to see where this file actually exists or if its generated at load time. If generated, check the database to make sure that you have the name correct, including character cases. Its also worth checking that the file has the right owner
that is visible to the web user.

No error
The first step is to check if your CMS has its own error log, some quick googling will confirm this.

Failing that, your best bet is to have a look at the community forums for your CMS.  Keeping a user on these forums is always useful even if you don’t have problems, this way you can see other tricks and tips and hopefully help out someone else who needs it.