There could be several reasons why you are unable to add or update WordPress plugins and themes:
- File permissions: Make sure that the file permissions on your server are set correctly. If the permissions are not set correctly, WordPress may not be able to write to the necessary files and folders. Typically, directories should be set to 755 and files should be set to 644.
- WordPress version: Check that you are using the latest version of WordPress. Older versions of WordPress may not support the latest plugins and themes.
- Conflict with other plugins: There may be a conflict between your current plugins and the plugin or theme you are trying to install or update. Try deactivating all other plugins and then installing/updating the plugin or theme in question. If it works, reactivate your other plugins one by one until you find the one causing the conflict.
- Hosting restrictions: Some web hosts may impose restrictions on the installation and updating of plugins and themes. Contact your web host to see if this is the case and if there are any restrictions in place.
- Corrupted files: Sometimes, the files may be corrupted during the download process. Try downloading the plugin or theme again and then installing/updating it.
- Memory limit: Your server may not have enough memory to install or update plugins or themes. Try increasing your memory limit in your WordPress configuration file (wp-config.php) by adding the following line of code: define(‘WP_MEMORY_LIMIT’, ‘256M’);
If none of these solutions work, it may be worth contacting your web host or a WordPress developer for further assistance.