How do I get strategy testing to work

Forex Trader
I have been trying to do strategy testing with my EA on a demo acct, but every time I run it, it shows 0 trades and 0 results. I downloaded the history files for the correct currency pairs, and I can see all of this on the History Center. I've tried every modelling method and every other setting and nothing works. After pressing Start, it apparently starts calculating and testing, but still with zero results. I've even checked the EA Properties and the Key is correct and all that. Does anybody have any clues on this? I just started with this thing. Thanks.