Free2Think4Me

You have a problem with the blue and/or brown pair in one or more of your terminations. Even if the wire is properly seated in the groove, look for nicks or breaks in the conductor where you stripped the outer jacket off, or maybe you accidently had the tool reversed when you punched the wire and it's cut on the inside, not the outside, or if you reused an end, check that the original wire didn't leave some of its plastic behind in the groove preventing a proper punch down.

Your computer may have a static IP address set in Windows that does not match the settings of the new router. A network adapter reset is easiest, or go to your network adapter properties and manually set your network configuration to automatic (DHCP)