How to Increase File Upload Size in PHP ?

You need to set the value of upload_max_filesize and post_max_size in your php.ini :

#Maximum allowed size for uploaded files.
upload_max_filesize = 40M

#Must be greater than or equal to upload_max_filesize
post_max_size = 40M

After modifying php.ini file(s), you need to restart your HTTP server to use new configuration.