PRB: Files uploaded by Flash uploader to PHP are corrupted

Description

When uploading files to a PHP server using Flash uploader (for example, when you use HTML5/Flash uploader in IE or, say, Safari on Mac), these files are corrupted and unreadable.

The problem may occur if you have PHP 5.3 or earlier.

Cause

Most likely it means that Magic Quotes feature is enabled on your PHP server. When it is on, it replaces all special characters in all the incoming data with an appropriate escape sequense, therefore the file becomes corrupted.

Solution

You should disable Magic Quotes. To do it, set magic_quotes_gpc directive in your php.ini file to Off.

Why only Flash version affected?

You may wonder why HTML5, ActiveX and Java uploaders work fine. The reason is that Flash uploader sends files a bit differently. Instead of uploading them as files, it sends raw binary data. If magic quotes are enabled, raw binary data is processed while files are skipped. That's why only Flash uploader is affected.

Edited by user Tuesday, June 4, 2013 7:25:18 PM(UTC)  | Reason: Not specified