Samsung S as mass storage [Is OK in tether]

[Android Question]

Won't show phone's storage info.
Dragged top bar down.
Big green droid turns to orange droid.
[Get caution - If you activate USB some devices may not work].
Have tried with both tethered and untethered USB.
Tried with and without connect to PC button
Still no mass storage.
[But works fine in tethered mode].