Don't just use software!
Ok, I won't argue that with 25k applicants and nobody is suitable, the way that the job was defined and posted is probably the problem. No question. But all that the Internet lets you do is reach more people. If they had posted it using traditional methods they might have had only 200 applications, but I'm confident that all of them would have been unsuitable as well.
The Internet lets you get applications from around the planet. People can submit their application for free, so they submit often. The traditional methods required paper, ink, and postage. They required you to get copies of job postings in that particular market by, say, buying a newspaper. The cost of resume blasting in those days was prohibitive.
But now it's free. I have found that the volume of applications when I'm hiring has increased, especially from overseas. You need to have *better* screening tools than you used to have. Manually screening even 200 applicants is prohibitive. So, you can't even just automate your existing process; you must make it tighter or you're going to be swamped.
As always, and I'm sure Toni would agree, make sure that your screening characteristics are bona fide!
