“I ace the phone interviews,” Mr. Adair said. “They say: ‘Your résumé speaks volumes. You could hit the ground running. It looks like you’re the perfect fit.’”“But you come in, and you’re D.O.A.,” said Mr. Adair, who is 71 and has neatly clipped gray hair. “You can see the look in their eyes.”“My wife says: ‘We need to get you a face-lift. We need to get your hair dyed,’” he said.Older workers are much more likely to wrestle with prolonged joblessness than younger ones, according to the Bureau of Labor Statistics. On average, a 54-year-old job hunter will be unemployed for nearly a year.Repeated inquiries can go unanswered, like space probes lost in a distant galaxy. In one of the most comprehensive studies, résumés were sent out on behalf of more than 40,000 fictitious applicants of different ages for thousands of low-skill jobs like janitors, administrative assistants and retail sales clerks in 12 cities. In general, the older they were, the fewer callbacks they got.