I was using 4.2.1 without any problem. Then the other day a window popped up when I opened the software, making me aware of an update. I selected to have the update downloaded once I closed the program. After I exited, the download began. However, the installation did not complete. I downloaded the newest net framework, but the program will still not work. The message says that the program cannot open. I tried to restore to the older version, but I was not able to--probably because during the new installation attempt it erased the older installation. Although I see the icon for the older installation, it will not open when I click it. I tried to download and install another fresh version and it failed. I tried to install an older version and it too failed. My operation system is Windows 7.