I had this problem too, and now I wonder if my file system is okay
I had the bogus 100% full message today too and had no idea what to do, so I alternatively powered down the expander, then the HD terminal, then both, until it went back to normal.
However, before I did that, I tried doing what it said and deleted some programs. At first it didn't seem to even react to the command to delete the programs, but eventually it did, in that the program disappeared from the list. But, the % full never went down even though I deleted things.
Like I said, I eventually got it to behave but now I'm worried that the deletes I did may not have been done properly. The program titles disappeared from the list, but what if the disk space was not properly released? Part of the reason I'm concerned about this is that before this error, when I was watching TV last night, the unit was 49% full. Then when it was having its 100% full hissy fit, I deleted a movie or two and a couple of other lengthy programs, and now it says its--49% full. I think it may have recorded one more episode of something last night after I was done watching, but I don't think it balances out, so I'm concerned that those deletes I did before the reboot were not done correctly.
Is there a way to run some sort of a file system check on the box, similar to the disk check in Windows that cleans up file system problems?