You'd prolly be on the safe side to get IE 5.5 or Netscape 4.78 (or Netscape 6 or 7 if you're feeling adventurous). Right now I've been using IE 5.5 and Mozilla 1.1 (a new browser that Netscape 6 & 7 is based on). I've never had that problem. It may be something else going on with your computer, too.
Next time you get that message, post the entire message here so we can check it out!
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