How to Fix the Theme Missing “style.css” Error

Funny story: as I may or may not have mentioned in the image captions last week, I’ve been helping a friend build a website. And naturally, as it so happens with these things, we came across this error: theme missing style.css.

I won’t lie; I spent a lot of time tinkering around WordPress, trying to figure out how to fix this issue. In the end, it turned out to be a rather dumb—silly, really—thing. So, that got me thinking that a lot of new bloggers may have also experienced this and hence, this blog idea came about.

So, picture this: you’ve just downloaded an amazing custom theme for your WordPress site and click “Upload New Theme” on Appearance. And just like that, there’s an error message that pops up on your screen: Upload failed: theme missing style.css error.

If this sounds like you’ve experienced (or are currently experiencing), don’t worry! In this blog, we’re going to look at this error in more detail, see how to fix it, and get your new theme up and running smoothly.

• Check out my blog post: How to Make Your Website More Mobile-Friendly?

What Does This Error Actually Mean?

The theme missing style.css error points towards not finding the styles file within the zip folder of their theme. I mean, yeah I had to provide the definition, why is this important?

Well, that’s because the style.css file is absolutely vital to your theme’s design. It meticulously defines your site’s layout, colour schemes, fonts, and the entire visual presentation. Without it, WordPress simply won’t know how to display your theme correctly, so it understandably refuses to install it.

Why is the style.css File AWOL?

There are several potential reasons why WordPress can’t find the “style.css” file:

• Accidental Deletion or Corruption: The file might have been accidentally deleted or corrupted during the download or even the upload process.
• Incompatible Theme: You might have inadvertently downloaded a theme file that’s not actually compatible with WordPress. It could easily be a theme meticulously designed for another CMS like Drupal or Joomla.
• Plugin Mix-Up: The zip file you uploaded might be a plugin masquerading as a theme.
• Incorrect File Location: The “style.css” file might be languishing in the wrong directory within the theme folder.
• Theme Package Issues: The theme file isn’t where it should be; it’s possible you also downloaded the themes licenses or other documents along with the theme file.

Fixing the Theme Missing style.css Error (6 Ways)

So, now that we know why this issue happened, let’s get down to fixing this error. Here are six ways to help you troubleshoot and obliterate that “theme missing style.css” error:

1. Double-Check Theme Compatibility

The very first thing you need to do is make sure that the theme you’re trying to install is actually designed for WordPress. Theme marketplaces, such as TemplateMonster, offer a vast array of themes meticulously crafted for different platforms, so it’s easy to accidentally download a theme intended for the wrong CMS (Content Management System).

How to check compatibility:

• Theme Page Details: Check the theme’s title, category, description, and software versions for telltale WordPress tags. If WordPress is tagged, you’re likely on the right track.
• Vendor Check: If you’re downloading from a theme marketplace, it’s always wise to double-confirm the theme’s compatibility with WordPress.

If the theme isn’t specifically designed for WordPress, you’ll need to hunt down a compatible one.

2. Rule Out Any Plugin Confusion

Be absolutely sure you’re not attempting to upload a plugin while thinking it’s a theme. This frequently occurs when you purchase theme extensions. The free Astra theme, for an example, has many add-ons known as Astra Pro. It’s really easy to mistakenly upload a plugin because the zip folder isn’t always clearly labelled as either a plugin or a theme.

How to avoid plugin mix-ups:

• WordPress.org: Go into WordPress to locate the theme or extension and find its official entry.
• Tags and Categories: Carefully examine the tags and categories to assess whether it’s listed as a plugin or not. Astra Pro, for instance, is meticulously categorised as a plugin.

3. Inspect the Theme Folder

If compatibility isn’t the root cause, the next step is to carefully examine the theme folder. WordPress themes typically arrive in a zip folder containing a multitude of files, including that all-important “style.css” stylesheet.

Here’s how to inspect the theme folder:

1. Extract the Zip File: Right-click the zip folder and then select “Extract All”. Choose a destination folder on your computer for easy access.
2. Open the Extracted Folder: Navigate with care to the folder where you extracted the files.
3. Look for style.css: Scour the newly unpacked theme folder for the “style.css” file.

• If you find the file: It’s possible it might be corrupt, thereby preventing WordPress from correctly reading it. Should this be the case, procure a fresh copy of the theme and attempt the upload once more.
• If you don’t find the file: It’s highly likely it might be misplaced somewhere within the folder structure.

4. Carefully Verify the File Location

The “style.css” file absolutely must be in the correct location for WordPress to recognise its presence. It should be situated in the theme’s root directory. The root directory contains the main folder, which also contains the all-important “functions.php” file. In simpler terms, when you open the theme folder, “style.css” should be immediately visible.

How to check and correct the file location:

1. Browse the Theme Folder: Methodically look through the other folders carefully nestled within the extracted theme folder, seeking the missing “style.css” file.
2. Employ the Search Function: To expedite the process, utilise the search function within the folder to search specifically for “style.css”.
3. Move the File: Once you locate the elusive file, right-click it and opt for “Cut”. Then, carefully return to the theme’s root directory, right-click once more, and select “Paste” to move the file into its rightful location.

Fun fact: we actually had this problem when we were installing our theme. Luckily, all we have to do was place the style.cs folder in the same folder as the rest of the theme and it worked!

5. Re-Zip the Theme Folder with Care

If you’ve already verified the theme folder and ensured that the “style.css” file is both present and correctly located, you’ll now need to re-zip the theme folder. This prepares it perfectly for uploading to WordPress.

How to compress the files:

1. Select All Files: Select all the files and folders carefully residing within the theme’s root directory.
2. Compress: Right-click the selected files and folders, then choose “Compress” or “Send to > Compressed (zipped) folder”. This will generate a brand-new zip file containing your meticulously prepared theme.

6. Upload the Theme to WordPress

With your theme folder now meticulously prepared, the moment has arrived to upload it to your WordPress site.

Here’s how to upload and activate the theme:

1. Go to your WordPress Dashboard.
2. Navigate to Appearance > Themes.
3. Click the “Add New” button at the top of the page.
4. Select “Upload Theme”.
5. Click “Choose File” and locate the meticulously prepared zip file of your theme on your computer.
6. Select “Install Now”.
7. Once the theme files have been diligently uploaded, click “Activate” to apply the theme to your site.

And that’s it! You’ve installed your all-new custom WordPress theme!

Alternative Approach: Upload via FTP

If you’ve tried all the steps I mentioned and you still see the pesky error message, consider uploading your theme folder via FTP (File Transfer Protocol) using a suitable client like FileZilla. This method can often be more reliable, particularly for larger theme files or when encountering issues with the standard WordPress uploader.

If you have no idea how to do this, let me know and I’ll create a blog this. Generally, the methods above tend to fix the theme missing style.css error but you never know.

At some point in the next coming weeks, I will be talking about how to install a theme on WordPress so watch out for that!