How to Protect SWF Files from Download?

Flash SWF files contain important Intellectual Property of a company or personal, but once they are on the web and available to the public, there is on way to prevent them from being downloaded.

Though you can use some JavaScripts or PHP scripts to hide the URL address of SWF files, but in Internet Explorer, all browsed files will be saved in its temporary directory, so they can still be found in this folder. And with SWF catcher software, most of them are free, you can easily find and display the SWF files.

So whatever the way you try to prevent the SWF files from download will not be fool-proof. The best way of SWF protection is to lock the allowed domain and then encrypt the SWF files.

With domain locking, the SWF files will only work on your own website. If they are downloaded,  they will refuse to play and display a warning message or just render as useless. By further encrypting, you can protect SWF files from being decompiled and modified.

SWFProtection comes with these two features: domain locking and encrypting. Its domain locking function can disable viewing SWF files from local computer and only allow SWF files being hosted on specified domains. The encrypting function will convert the whole SWF file to binary data, then encrypt the data and embed it into a new SWF file. In this way, all contents in the SWF file, including Actionscripts, images, sounds and animations will be protected. The program will enhance the encryption further with Actionscript obfuscation.

This tutorial will guide you how to protect SWF from download with SWFProtection.

  Download and install SWFProtection.The software comes with a free trial, so you can check it out before you buy it.

  Launch the software, click the button "Add File", browse the SWF files need for protection, add them to the file list.

  Click the "Domain Lock" tab, check the options "Disable viewing SWF files from local hard disk" and "Only allow SWF files hosted on domains", then click button "Add", and enter your website domain name. If you want to display some warning message when someone tries to view your SWF file on local computer or upload it to his or her website, you can check the option "When domain is incorrect" -> "Display message", then enter the HTML formatted text in the input box. Hyperlinks are supported in the warning text.

  Click the "Output" tab, define how to rename and where to save the protected SWF files.

  Click the button "Protect". And congratulations! You have successfully protect the SWF files.

The following Flash SWF file is created with MTool Flash Banner Maker and protected by SWFProtection, you may download it and have a test of the protection.