Nokia 5300

So here is a strange problem, I lost my instant messenger, the icon no longer appears on the menu. I honestly have no idea how it happened, I'm assuming that some magical force took it out when the phone dropped that one time. Maybe it was faries or something, I have no idea. All I want to know is how to get it back in. I know that it can be done by hooking up the 5300 to my PC but I don't know what software to get and where to find the instant messenger for reinstallaion. Any help?