i think this 600 of mine may be a lost cause but just in case one of you geniuses can think of some miraculous way of fixing it, here's what happened.
tonight i was trying to transfer a book using calibre (i've never used the sony ebook library software) and i got a strange error that the file could not be read, or something (sorry, i didn't think to note down the exact message at the time). i clicked to check the internal memory (in calibre interface) and it appeared empty. no doubt communication between pc and device had stopped partway through the transfer, because it had mounted ok and displayed the books on the internal memory when i first plugged it in.
i unmounted it as usual but when i unplugged the usb cable i got an error message : "Internal content invalid. Formatting in progress" ("contenu à l'intérieur invalide. Formatage en cours.") with an ok button. when i touched the ok button, the bar at the bottom of the screen displayed "Formatting internal memory in progress" ("Format. mém. interne en cours") for a while, then it went to the home screen displaying zero content in all categories.
it happens i had a backup of all content which i made saturday before the latest paris meetup (straight copy of all files in user memory via windows file explorer), in case somebody deleted accidentally a book containing notes, so i decided to restore it. i had some trouble getting it detected. when it finally mounted i began the transfer of my backup via the windows file explorer. it seemed to have some trouble ("estimated time to finish : 170 minutes" although it decreased after a while) and partway through there was an error ("damaged content" or something like that) and when i tried to look at what had been transferred so far i discovered that it was no longer connected to the pc (i couldn't explore the disk, it appeared empty). when i unplugged it, it formatted the internal memory again.
i thought perhaps i could fix it if i reinstalled the firmware update, but (once i finally got it to be detected...) it told me the firmware was already up to date, and didn't install anything.
background : the usb connection has been unreliable almost since the beginning, meaning that often when i plugged it in it wasn't detected at all, or incompletely (meaning sometimes the computer would see a disk but not go so far as to read it, and if i tried to open it in file explorer it would appear empty). it got worse about 2 months ago and wasn't detected at all or even gave me usb malfunction errors. i updated the firmware to version 1.0.01.08040 and since then it has been more reliable. i have no idea whether this is related or not.
it has spontaneously reset itself once that i remember, while it was in sleep mode. i don't know why.
it has never been dropped or taken any kind of hit since i've had it, and i have never unplugged it without unmounting it first ("remove usb device safely") with the exception of the times when it refused to be detected (no device appeared in the device manager, so i could not unmount it).
it's only 3 months old (i got it in late september), and given the erratic usb problems and now this, i'm getting the impression that i got a defective unit. i never had any similar problem with my 700, it only choked once that i remember and that was my own fault (20mo .rtf file. oops). i think i am going to try to take it to the sony shop and exchange it, although i anticipate some trouble since it was purchased in the US (i guess it's always a gamble to buy something overseas and sometimes you lose.
). any suggestions before i go and try to convince sony to give me a new one ?