May be you have often came across this error when you have tried to change Password of a user even though you are logged in as root user or error like can’t change read only file when you tried to change the permission of a read only file even though you are root user but you are not able to change permissions on a file,this sounds quite different as root user has all the privileges.
Well here is the solution to this…
Login as root user and use this command:
$mount -rw -O remount /
This will work!Here basically you are remounting your ‘/’ directory giving read and write permission on it. 🙂