WebRifle® is based on VB5 Run-Time Service Pack 3. Therefore, if you don't have the VB5 Run-Time, the WebRifle® setup program will inform you. Only in this case download the VB5 Run-Time and install it before WebRifle® (usually the Run-Time is not necessary for Windows® 2000/XP or above).
WebRifle® needs Internet Explorer® 4/5/6 with Active Desktop component installed, Windows 95/98/NT/ME/2000/XP,  10 MByte HD free space and WinZip 6.3 or above.