How to fix missing the style.css stylesheet error?

A common error that can occur when installing a WordPress themes is “The package could not be installed. The theme is missing the style.css stylesheet” error message being displayed when uploading or activating the WordPress theme.

This error means you are uploading wrong ZIP file, You need make sure you are uploading xtra.zip file.

Upload the Installable WordPress file via admin area

1. Log in to your WordPress admin area.
2. Browse to Appearance > Themes.
3. Click on ‘Add New’.
4. Click ‘Upload’.
5. Browse and select the theme zip file to ‘Upload’.

Upload Via FTP

1. WordPress files can also be uploaded manually via FTP.
2. Upload the files to /wp-content/themes/ folder on your server.
3. Login to your WordPress admin area to change the theme.
4. Check out the guide on WordPress.org here.