When Sucheta Dalal and Debashis were doing proof reading in computer, Windows XP logo was visible which was launched in 2001 and was not available at that time.
When Sucheta wraps up her manuscript of her book "The Scam", Debashis is sitting next to a computer running Windows 7. The Scam was published in 1993 while Windows 7 didn't debut till 2009.