I did some trial on command line and creating a user account from it, then I logged off and logging to that newly created account (let us call it newaccount). Then I mounted one of my drive (I named it as LOSSProp) from it. After that, I returned to my account (myaccount), and then deleted newaccount. But then I lost my permission to mount mydrive and I can't open it anymore. Then I googling for a while, looking for a solution to fix it, I had tried
sudo chown -R username:username /media/mydrive
and using GUI by nautilus in sudo mode. But still I can't change its owner, it still owned by newaccount which I had deleted it.
How do I fix it?