General :: Unable To Write To NTFS Pen Drive

I am having a problem writing to an NTFS pendrive. I have created the NTFS pen drive in the following way:

Code:
fdisk /dev/sda
created the label with 'o', then written the table with 'w'

I've then gone into fdisk again :
Code:
fdisk /dev/sda
started the partition creation with 'n', and chosen 1 partition '1', then written that with 'w'

I then used mkntfs to format:
Code:
mkntfs /dev/sda1
The blkid command gives me this output:
/dev/sda1: UUID="58CEA9511D6BCEFA" TYPE="ntfs"

I can mount the pendrive (as root) with:
Code:
mount -t ntfs /dev/sda1 /mnt/pendrive
and the mount command output:
/dev/sda1 on /mnt/pendrive type ntfs (rw)

I have changed the permissions on /mnt/pendrive (while mounted) to 777, owner/group=root. However, when I try to copy something to the drive I get this error:
cp: cannot create regular file `/mnt/pendrive/file.txt': Permission denied