Disable WordPress 2.5 Flash Image/Video/Media Uploader with Plugin

WordPress 2.5 features a new media (including image, video and file) uploader that built on Adobe Flash technology which supports multiple files uploading to the gallery at one time and upload progress indicator bar. Unfortunately, the media uploader has numerous bugs and problems, which basically make the Flash uploader not working, or not successfully uploading the files.

There are a few symptoms for the broken Flash uploader error. For example, blogger can adds the files to upload, but nothing happen or progress to upload the selected files. Sometimes the upload process manages to get to “Crunching” but stop working after, or comes out with HTTP error, or even worse, freeze and crash the browser to not responding. Other reported problems including the the add media buttons disappearing or not showing up.

WordPress Support has listed several steps to check and fix the possible problems that cause user cannot upload photos, images, videos, music and other media files in WordPress 2.5. If the Flash based media uploader does not work after whatever effort, workaround and solution been done, including some bug fixes, such as disable conflicting plugin and bypass mod_security to try to solve the error and issue, there is a plugin to force disable (or later re-enable) the Flash uploader.

To enable the Flash media uploader to be disabled via plugin, a filter has to be added to Flash uploader (only on WordPress version 2.5.x, as the change is set to implement in milestone version 2.6). To do so, edit the \wp-admin\includes\media.php file using your favorite text editor directly by logging in to server or locally (has to be uploaded and overwrite replaced the original media.php file). Change the following code at around line 765 to 770.

Before:
$flash_action_url = get_option('siteurl') . "/wp-admin/async-upload.php";

// If Mac and mod_security, no Flash. :(
$flash = true;
if ( false !== strpos(strtolower($_SERVER['HTTP_USER_AGENT']), 'mac') && apache_mod_loaded('mod_security') )
$flash = false;

After:
$flash_action_url = get_option('siteurl') . "/wp-admin/async-upload.php";

$flash = apply_filters('flash_uploader', true);
// If Mac and mod_security, no Flash. :(
$flash = true;
if ( $flash && false !== strpos(strtolower($_SERVER['HTTP_USER_AGENT']), 'mac') && apache_mod_loaded('mod_security') )
$flash = false;

Then, download the no-flash-uploader.php, and upload the PHP file to \wp-content\plugins\ directory, and activate the plugin via WordPress administration page. After activating to disable the Flash media uploader, the uploader will no longer make use of Flash technology, and all advanced features that come with it also been disabled.