Northampton become the fourth managerial post of Boothroyd's career despite his relatively young age with the former Watford, Colchester and Coventry boss dropping into the basement division for the first time.
However, he told the club's official website: "I think this is a real positive step for me. It is a big job and a big challenge, but if it was easy then everybody would be able to do it and it wouldn't be an interesting job.
"I have used the word 'potential' a lot because I think Northampton Town has got massive potential, but, at the moment, they are underachieving. But whenever you go to a place and things are not going so well it makes it all the more positive when things do go right.
"I am really looking forward to what should be an exciting challenge. I look at the ground, what it is now and think to myself what it could be."