[loudube]

I sometimes find that 5-1, 7-1 or 9-1 simply disappear and by reading the caption in HDTV Signal Strength "Please adjust your antenna to maximize the number of channels....." I am lead, erroneously to believe that I could recover the channels. But scanning and rotating the antenna and scanning again and again has no effect whatsoever. It looks like that scan never does anything. I have stoped it many times right at the beginning and found nothing missing.
My question is is deleting a line up and rerunning Auto Scan the only way to recover missing chnnels?