For website owners, using a custom theme enhances the overall look, feel and style of their websites.

Usually, theme installs go pretty well. Sometimes, it can result in errors.

One of the common errors that we see as a part of our Outsourced Tech Support for web hosting providers is  “Bad or missing configuration file”.

Today, let’s take a look at the top 2 reasons for this error and how we can fix it.

Causes for ‘Bad or missing configuration file’

This error pops up when you try to install a custom theme from your Prestashop Back Office(admin area).

The 2 major causes are:

1. Theme not compatible with Prestashop version – Some themes may not be compatible with your Prestashop version due to missing libraries, templates, functions, etc.
2. Corrupted template zip file – Usually, you will get Prestashop themes in zip format. Prestashop expects a default directory structure for these template files. We’ve seen developers create custom theme files that are non-complaint with these Prestashop standards. Prestashop considers this as an invalid file and throws this error.

How we fix ‘Bad or missing configuration file’

To fix this, we can use 3 different ways:

1.Get a theme compatible with the Prestashop version.

If your theme is not compatible with Prestashop, you need to get a theme that suits your Prestashop version.

You can verify your Prestashop version using the below methods:

• Go to Prestashop Back Office > Advanced Parameters > Configuration Information.
• The file “/config/settings.inc.php” lists the Prestashop version on the line that begins with “_PS_VERSION_”.

define(‘_PS_VERSION_’, ‘1.6.0.8’);

You can verify the theme version and its compatibility range from the file  “theme.yml”.

At Bobcares, we cross-check the above files and choose an alternate theme that fits the Prestashop version.

2. Correct the directory structure of your zip file

Prestashop looks for a default directory structure like this.

If any mismatch found, it will reject that file.

We see cases where the custom theme files non-complaint with this set format.

In such cases, we will extract the files to get a directory structure similar to the default theme and zip it once again.

This way we will create a valid ZIP that can be uploaded to your Prestashop.

3. Uploading in case sensitive systems

In some templates the “Config.xml” file is included as “config.xml” (C not in block letters). This is going to fail when you upload the zip file to case sensitive systems like Linux. In such cases renaming config.xml to Config.xml will work.

Conclusion

You can come up with “Bad or missing configuration file” at times when you install a  custom theme in Prestashop. Today, we’ve seen the top 2 reasons for this error and 3 ways to fix this.