Hi Vince.
Have you managed to swap out the drive yet and if so has it cured the problem or is it too soon to say?
I too have just started getting this for the first time this week.
My box is getting on a bit now, bought in Nov '08 and to be honest I think it's on it's last legs.
In recent months, the box has taken to refusing to start recording timer events even though it wakes up 15 minutes before the programme is due to record. I've had to resort to setting the box to wake up early in the evening so that it's already on as each timer event is encountered. This cured the problem although isn't ideal.
I've had a couple of lockups and when powering off at the back, waiting and powering on again, the box boots and displays a channel but the programme banner remains on screen and all device and remote buttons are unresponsive. The only way past this was to hold the power button on the front whilst booting.
Finally, it's taking a while to boot. Sometimes it's less than a minute but sometimes it's nearer five minutes.
This latest problem though is possibly the most annoying as I lose all of the programmes listed in the library seemingly at random. I can be watching a live programme, iPlayer or a programme I've previously recorded, go into the library and it's empty. If a recording has been taking place in the meantime, the recording stops mid-programme even though the REC indicator is still on the display. If another time event occurs whilst in this state, the REC indicator doesn't appear. Also whilst like this, you cannot pause the current live programme.
At first I thought it was the drive but although the library is empty, I can still view the contents of the music partition and I can still see and play all programmes if I connect via FTP/Samba/Twonky. By the way, this latest problem occurred whilst using the latest firmware without the Media extras installed. I only installed that this week as a test to see if it was just the box software itself that is somehow losing access to the video partition. The reason why I'm posting in this thread is that a couple of times I have been deleting programmes and it's failed with the files restriction message. At this point as per above, the entire library disappears until the next reboot.
I'm presently copying all programmes off the box so that I can reformat but I'm disheartened that by the sound of it this problem can reoccur a couple of months later.
Time for a new box maybe.