Oh. I have no idea if this is worth saying but I had a starcraft CD before which I've used in my old computer way back when we did not have a router and I was able to host games. The thing is, I've accidentally given my cd key to someone there in battlenet and my CD key could not work anymore. Of course, I was unaware that a banning rule was in placed on giving the CD key to someone as I was too young to read any rules about starcraft.
Long story short, I bought another CD key and it is this one and I am using it with this new computer with a wireless router functioning to give me internet.
It probably seems like the problem is my router isn't it? =/