LetterBox 1.2 Eval Download InstallLB.exe - LetterBox Evaluation (396 kb) The LetterBox Eval is an almost fully functional version of LetterBox. The LetterBox Eval has restrictions on the regular LetterBox printing and saving functionality, but still allows you to test and use LetterBox to get a good feel for its abilities. Read the following instructions to download and install the LetterBox Eval. LetterBox Eval Installation Instructions: 1. Download InstallLB.exe by clicking here... Download Now 2. Run the file InstallLB.exe file on you machine once the downloaded is complete. 3. The installer will provide simple instructions to complete the installation. 5. LetterBox can be launched from the Windows Start menu.