Downloading and installingAIM

Somehow my daughter screwed up our AIM messenger. We think it happened during upgrage. I uninstalled and reinstalled and to no avail. When I install it, and click to open it it puts the little icon down on my taskbar but won’t open then icon disappears. Any idea. I then upgraded Netscape to the new one which I don’t like and have that messenger, but it isn’t the same. I would like to go back to my older netscape and get her her original messenger back. Thanks