Re: constant errors file system
Usually the symptoms of a bad drive are that you (even with sudo) do not have permission to write anything to the hard drive because, as redmk2 says, it automatically remounts read-only. One problem with that is that there is no permanent log that anything went wrong (and could be why apps think they have not shut down properly). The only way to check for such errors is to look at dmesg when something strange happens "before" shutting the computer down.
My Linux partition is at the far end of a 1 TB drive, which seems to have started going bad months ago when I started having write permission (read-only) issues. Although, e2fsck with the switch to mark out badblocks from Ubuntu on another drive (SSD) helped for a few months, eventually it started getting more errors. So I used Acronis to image Win7 partitions (which had not gone bad yet) and recreated them on a new drive. And I reinstalled Ubuntu 12.04.2 and copied my old home partition to that.
A hard drive reserves some space to transparently replace (remap) good sectors in place of bad sectors. But once all the error sites are used up, it is never going to get any better, just worse. And it should not be trusted for anything essential.
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