I am using Mountain Lion on this MacbookAir, and my browser is Safari. I have been sent a link to a pdf-file. When I steer the mouse-pointer over the link, the pointing-hand image does not appear, and clicking the link has no effect. However, if I steer the pointer a little below and clear of the link, the image does appear, but flickering so fast that one cannot click to open the link. The website-manager who has provided the link insists that he can open the link with Safari, provided that plug-ins are enabled. They are enabled on this computer, too. When I go to MacintoshHD/Library/Internet Plug-ins, I see: DivXBrowserPlugin.plugin ebldetect.bundle Flash Player.plugin flashplayer.xpt Flip4Mac WMV Plugin.plugin Flip4Mac WMV Plugin.webplugin iPhotoPhotocast.plugin JavaAppletPlugin.plugin npdivx.xpt nsIQTScriptablePlugin.xpt Quartz Composer.webplugin QuickTime Plugin.plugin Silverlight.plugin Is 'Flash Player.plugin' the culprit ? What about 'flash player.xpt' ? If I go to Safari/Help/Installed plug-ins, and scroll down to the very bottom of the list, I find WebKit Built-in PDF: application/pdf. Can any kind person tell me how to sort this out ?