If you are trying to install the software utility on a computer running on Windows Vista then you will need to disable User Account Control (UAC) to run the software.
Follow the instruction below to disable UAC in Windows Vista.
Open your Control Panel and switch to Classic view. then open: “User Accounts” Click User account control on or off uncheck UAC and restart your Computer.
Then re-launch the application, now you would be able to access the drive and can recover data from it.