You could have downloaded ProofLocker 1.1 from our software library for free. The actual developer of the program is RCMedia Services. The most popular version of the ProofLocker is 1.1. The program's installer file is commonly found as ProofLocker.exe. ProofLocker is included in Security Tools.
From the developer:
ProofLocker , the first product to utilize PixLocker technology (from RCMedia Services), is created for the professional photographer or Studio. Designed BY photographers, FOR photographers, ProofLocker will eliminate your proofing expenses while at the same time, guard your images from theft. Most systems simply earmark your images so that you can prove ownership. ProofLocker prevents acquisition in the first place.
You may want to check out more software, such as ToolbarCop, Discover It! or Encryption Anywhere Hard Disk Client, which might be similar to ProofLocker.