cant modify files on pendrive

[fevel]

im using knoppix 3.8, plugged in the usb pendrive, and it showed it as uba1 but i cant modify, erase or add any files to it. Ive tried
chmod 777 /mnt/uba1 and then restarted kde but it didnt work, I also tried unmounting and mounting it again, and nothing. I tried adding the word rw after
"exec,"in the fstab and nothing.
Can someone help me...i would like to take my files around with my usb device

[Markus]

Try these:

markus@mrk-fujibox:~$ ll -d /pen
drwxrwx--- 2 root users 4096 Feb 28 16:35 /pen

markus@mrk-fujibox:~$ la /pen
total 8
drwxrwx--- 2 root users 4096 Feb 28 16:35 .
drwxr-xr-x 26 root root 4096 Mar 5 17:37 ..

markus@mrk-fujibox:~$ grep pen /etc/fstab
/dev/uba1 /pen vfat noauto,users,exec,noatime,umask=000 0 0

Note that the pendrive is unmounted here.