I can write on my flash disk now. How? Simple… You must log on as root or super user mode to access it. if you need copy or move the files or folders, my suggestion is : DO IT in SUPERuser MODE. For example, you want to copy or move x.txt to your flash disk, this is the commad
root@computername:/home/username/Desktop# mv x (destination) // moving x.txt to destination
if you want to directly open and save new file in flash disk, first log on as root, then go to /mnt/usb or /dev/sdb . Then…
root@computername:/mnt/usb# nano x // in here, i go to /mnt/usb then opened x in program nano. You can change with the other program that appropriate with the extension of the file
Then save it!