How was everything hooked up, was it from the cd player directly to the tape recorder, or was it through a receiver or pre-amp, give us some information so we can help you.
From CD to Reciever and from Receiver to cassette deck. Thing is, I have recorded many times before (not lately) and it worked fine. Could it be that I bumped something and knocked a connection loose?
That could be it, check your connections from the deck to receiver, it sounds like that may be your problem, especially if you move the receiver often to dust or clean behind it.
If the cables are all ok, the heads are clean, and if it's an older deck with mechanical switching, it could be a dirty Play/Record Switch. Toggle between play and record repeatedly and see if it starts working. You may have to 'pop the top' and go after the offender with spray electronics cleaner. Tom