On some Windows installations it appears that you need to specifically run the installer as Administrator. This should be unnecessary but it does solve the issue for many users.
To run as Administrator simply right-click the installer, e.g. AgentRansack_828.exe, and select "Run as administrator" from the context menu.
If that fails you can generate an installation log file by running:
agentransack_828.exe /logfile "C:\Users\Me\Desktop\ar_install.txt"
Please send it to Mythicsoft support for additional assistance: support [at] mythicsoft.com