Most likely, it has to do with the equipment being used but nobody would know unless you told us what. Could also be simply that drivers were installed or drivers were not installed. Again, something you'd have to reveal.
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When I am on a web page and press the right-click key (which key is to the immediate right of the Start-button key) on the keyboard of my Windows XP computer, most of the time I get the right-click menu but sometimes I get a "Macromedia Flash Player 6" menu (of sorts). What can I do to my computer to stop getting this Macromedia menu. Thank you very much.