When I started pretty much all hires were 90 days temp to perm. So I went through an agency to be hired on. The recruiter gave me a list of questions they would ask, what is an outlook pst, a template .dot file. Then a mock user to you agent situation where the goal is to either make you crack and get angry or break down and cry. So to see how you handle an angry caller. At this point in this companies place in the market/profit happiness, they only care about how you will search in the knowledge base or google for the technical answer and handle an angry caller because you really have no technical experience and you don't lose your cool when it gets obvious you are incompetent at what you do.
Either way keep your cool and answer all questions with I'm no completely sure but I would search the knowledge base or online and you're golden. Show up everyday on time and they'll never fire you because you're hired on at $15 an hour and if you take 2-3 calls an hour and create a ticket, you're making money for the company.
They used to require an a+ certification after 90 days, but now it's obvious they don't/can't expect it with the talent they hire on these days.
If you can keep your cool and act like you know enough to get through the interview, then you're good for CompuCom. Just remember that if you are good enough to get your A+ and learn from what you do there, you don't belong there and get out after 2-3 years max.