Record the uploader’s exact message and distinguish a transfer failure from a file-type restriction or image-processing failure.
Steps
- Try one small, ordinary image through Media → Add New. Compare its size with the maximum upload size shown on that screen.
- If the small file works, inspect the failing file’s actual format, dimensions, size, and integrity. Renaming an extension does not convert the file.
- If uploading is unavailable, check your role’s upload permission. Standard Contributors do not receive the same upload access as Authors or Editors.
- For a browser-only failure, preserve work and retry with the file picker or another current browser. Use a fallback uploader only if the interface offers it.
- For failures across small files and browsers, check account storage and the relevant application/server error at the upload time. An image that uploads but cannot generate sizes may require a different diagnosis from a rejected HTTP request.
- After a correction, upload once and inspect the Media Library before retrying to avoid duplicates left by partially completed attempts.
Check the result
Insert the uploaded item into a draft and verify both its displayed version and original file URL.
Before you continue
Do not enable unrestricted file uploads or make upload directories writable by everyone. Share diagnostic excerpts privately and remove credentials or personal information.
Documentation for this guidance: wordpress.org — media add new screen; wordpress.org — roles and capabilities; wordpress.org — site health screen.
