The safest way to download legacy versions is through the FL Studio Installer Archive on the official Image-Line forums. Registered users can access the last stable installers for major past versions here.

Official versions of FL Studio 10 (released March 29, 2011) are no longer available for direct public download on the main Image-Line Download Page

Downloading a cracked FL Studio 10 zip file is software piracy. It violates the intellectual property rights of Image-Line.