The program was designed to run under the Windows XP Service Pack 2 Operating System. Theoretically you might get it to work on a Windows 8 operating machine. After you've installed the program, right click on the Cashflow Manager icon and click on "Properties". Go to the "Compatibility" tab and check the box next to "Run this in compatibility mode" (you should select Windows XP Service Pack 2 from the list). In the same screen you should also check "Run as Administrator" box. Click "Apply" and then "OK" and it might work.