***SOLVED***
Just wanna share my experience:

I don't know if somebody solved this problem before:
"UNABLE TO CONNECT ,FILE SYSTEM NOT AVAILABLE"
But from my experience I can see that this is not a problem that avoid from using H-E-N.
For those having this error follow this steps::

1-Unplug any USB cable from the phone.
2-Open h-e-n and choose the wanted speed.
3-Click on **VBUS BOOST ON** and wait for 10 sec.
4-Connect the USB flash driver tho the USB cable. Then plug the latter into the phone.Wait for 10 sec.
5- click on **ENUMERATE** Wait for 10 sec
6-then click on **MOUNT**]

And here you go