[Users] Windows 7 networking problem

Hi, Ive installed Windows 7 guest and when I connect Virtio NIC it only gets IP address from DHCP, but I can not communicate, even not ping to network. I used red-hat packaged virtio driver in version 1.6.3 and than 0.1-52 from linux-kvm.com, but the result is the same. (I restarted Windows several times). My Ubuntu guest works great. What do I wrong? Thank you ;-)