Try repositioning your antenna to a different location, prefrebly close to or even in a window if you can and then rescan again. Although KARK's virtual channel is 4, their actual channel that they broadcast their signal on is Channel 32, according to their FCC public inspection files record. Channel 32 is in the UHF band. UHF band signals are harder to receive if your antenna's located indoors. Putting it in a window usually helps the UHF band signals get to it much better. I personally have some 75-ohm coaxial cable run from my tv to my window and then use a female-to-female F coupler to connect my antenna to it.