you have to unmount partition and run it like this:
However the first can be tricky. I suggest the following procedure:PHP Code:e2fsck /dev/discs/disc0/part1
switch off router
disconnect usb device to be checked
switch on router
30 sec later connect usb device
then do
do similar operation for all mount points on this device which you can see byPHP Code:umount /opt
after that run e2fsckPHP Code:mount

