I have a DELL computer with the windows 7 operating system running environment. Which runs very good. Few days ago I installed a third party software for the image viewing purpose but the problem is the software is not the full version, it is a trail version software which is not working now. Whenever I tried to open the application it ask for the serial key, I found in everywhere of the serial key, but none of these are worked. Can anyone tell to how extend the trial period of the software that are having the trial period expired?