That's why the issue can occur when trying to do very different tasks like :
- 1. Uploading a theme or plugin
- 2. Publishing posts or pages
- 3. Creating tags or categories
- 4. Inserting an image into a page or a post
- 5. Customizing a theme
- 6. Updating WordPress core or plugins and themes
- 7. ...any other administrator tasks
This documentation reviews the most common scenarios and fixes for this problem.
Before trying any other solution, we recommend to clear your web browser's cache and cookies.
- 1. You are trying to upload a theme or plugin with an incorrect file format
You are trying to upload other than ZIP Compressed version. Other compression formats are not supported while uploading a theme or a plugin in wordpress. When installing any plugin or theme in WordPress, the file should be uploaded as .zip file.
- 2. Problem with PHP memory limit or upload max size
The problem may also occur when either the max post size, max upload size or PHP memory limit defined for WordPress has been exceeded. You can either fix it by yourself if you have intermediate server skills, or ask your hosting company to do it for you.
- 3. Plugins or theme problem : deactivate all plugins and revert to a default theme
If the previous solutions did not fix the problem, try to deactivate all your plugins from your WordPress dasboard, and revert to a default WordPress theme like Twenty xxx . Then reactivate your plugins one by one until the error messages shows up again. This way you'll be able to identify which plugin is responsible for the problem. If you don't have acces to your WordPress admin dashboard, you might need to remove your plugins by using an FTP client.
- 4. Generate a new set of security keys