Ok so I was watching the Oscars last night on my Comcast HDDVR. I wasn't actually going to record it or anything but at one point I wanted to go back to something. I hit the rewind button and what happens? A big circle with a line through it comes up!! So then I tried to just record it an nope, wouldn't let me do that!! Did anyone else experience this? I was sooooo mad!! The TV, Movie and Record industry are really trying to screw things up!!
I don't think it was a "no copy" thing you ran into. I got the same thing on Friday when I was supposedly recording BSG, couldn't FF or REW just got the anti symbol like you did. I came back after it "recorded" and it wouldn't play back. As soon as I hit play on the remote it asked if I wanted to delete. I then recorded the 1:00 a.m. showing fine. Probably just some hiccup with the system.
Sigh... to the posters, which "Comcast DVRs" do you have? They ship at least the DCT-6412 w/MSTV and iGuide and the SA8000 w/SARA to name a few. I have no idea how many other ones they use depending on the area.