UR44 and MIDI

Hello!
I can’t find an answer to this anywhere.
The thing is that with my previous sound card, I’ve been using Guitar Pro 6 with it midi sound sinthesizer, the one that comes with all sound cards and interfaces. I can not make it work the same way with my ur44. Either if I use windows media player and I open a .mid file, it doesn’t sound, and it use to with my previous sound card. So is not something specific about Guitar Pro, what I mean is, do I have a sinthesizer with my ur44 or not? If yes, how can I make it work properly.
Thanx a lot, everybody!