Sometimes when you try to add a file using Media Library or Post Editor, it displays an error message: “Maximum upload file size: 24M” This might create a problem for you if you want to upload files or photos that are larger in size.
Solution
The solution to this problem is to go to your hosting control panel and edit the php.ini file. Add or Edit these lines in order to increase the maximum file size to 32M:
upload_max_filesize = 32M
post_max_size = 32M