AceHTML is Windows XP compatible. It was not officially supported on Windows 7 or Windows 8, and it is expected not to work properly in Windows 10. However, if you need to use the program with Windows 10, you can try running it in Compatibility Mode. For that to happen you should find the main .exe file or shortcut you use to launch the application, right click it and select Properties. After the Properties box has opened, click the Compatibility tab, then tick the box labelled Run this program in compatibility mode for and select Windows XP, as the program was designed for this version of Windows.