I first discovered this with LXDE, and thought it was a problem with that DE, but now I find I have the same problem with all installations on my Dell mini 10v, but on none of the ones on an old iBuddy laptop.
Simply I cannot change ownership or permissions of any files or folders on this computer in LXDE, Minime 2010, or PCLOS 2009.2 KDE3.5. (There is a similar set on the iBuddie, and all are OK).
Since the iBuddie has a disk drive (flaky but works most of the time!) they were all installed from live CDs. The Dell doesn't have any sort of drive so I made a live USB from the 2009.2 live CD and used that to install this on the Dell. Then I used the same USB drive for LXDE and Minime 2010, replacing the isolinux folder and livecd.sqfs from their respective CDs.
I have noticed strange permission problems from time to time, but yesterday discovered that chown and chmod seem to be disabled on all these installations. The commands seem to work, no error messages, but the users and permissions are unchanged. The graphical methods in the file managers don't work either, but I presume they are using chown and chmod themselves.
I don't know enough to know what the problem might be, but reading these pages I wonder if is is something to do with partition permissions? If so can I change them?
I'm thinking of buying a standalone USB DVD RW drive, and would then be able to install from disk, but I really don't want the bother of having to customise my installations all over again