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As a matter of interest, have you been able to record from any other source on your Panasonic, such as from a VCR or a terrestrial TV broadcast as the source? If you are able to record from other sources, but just not your HD box, the issue you mention indicates that the channel you are trying to record has a copy-never flag, which means that recording equipment capable of recognising this flag will refuse to record this channel. Unfortunately, your recorder is fully compliant with anti-copy measures.
If you cannot record from any source to its hard drive or you can record from your HD box to a recordable DVD disc, then the issue is likely caused by a data corruption on your hard drive. In this case, back everything you want to retain on its hard drive to DVD and format it.
Finally, if only your HD-box gives this issue, try recording off a couple of different channels such as a news channel, which is very unlikely to have a ‘never-copy’ flag. If all channels give this issue, then it is likely that your HD box is embedding a ‘never-copy’ flag into its output. If this is the case, you will need to contact the place you got the HD box from to see if they have a solution or if this may be a fault with your box.