It seems that this program was discontinued. Because of this, the developer didn't released an update for it, to make it compatible with Windows 8. However, there isn't any information about the error that you encounter. To overcome this, install the program using Compatibility troubleshooter. To start this service, go to the Start menu, in the search bar type Compatibility troubleshooter and press Enter. After the tool is opened, follow the steps provided to complete the installation process. If the same missing file error is encountered, I suggest to install Malwarebytes and perform a full scan of your PC. Also, you can try to restore your computer to a previous state in which the error wasn't encountered.