It means the website has some error in the source code and IE feels like it needs to inform you. It's annoying.
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I've never, ever gotten any kind of error like that at all from IE. And I think that you having a '-' for the number of unread e-mails means that noone likes you and you have no new e-mails (or friends)*.
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There's an option somewhere to prevent it from making popups. Probably labed as "javascript debugger" or something. (edit: rereading, i guess you don't get the popups, just a little icon... nothing to worry about, it just lets you know something on the site broke so if a button isn't working, that may be why.)
It's usually the site, though you could cause them yourself by running js functions that haven't been downloaded yet, if your connection is slow enough.
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Yeah you're real funny jackass.
The presence of a happy looking smiley usually indicates a
joke.
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Yay, reconciliation! Anyway, it looks like this thread has served its purpose...
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