Shockwave Player problem w IE & Netscape

I have the shockwave player plugin loaded on several computers running both Internet Explorer and Netscape. On all of the computers the plugin does not function corrrectly. However I have it installed on several other computers where only Internet Explorere is loaded. On the computers where only Internet Explorer is loaded the plugin performs normally. I prefer Netscape so I really need to some help here. I need to make it so that both browswers support shockwave content. Help!!