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Unless your customer controls a network on which he supplies the O/S, I don’t believe that statement. Even pretending that it’s true, users of WinXP are not limited to IE8 (asserted because ownership of WinXP seems to presume one will use IE8).
Suggest that your customer support his [marketeer’s] claim with data 
.
I can tell you first-hand that Chrome no longer supports WinXP and several other “essential-to-me” applications no longer support WinXP… they won’t install. You and your customer are expending time and money supporting a dying horse.
One of you has to be sensible about the marketing value of IE8 users. I do not for one minute believe that the ROI is there.
my
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