help emergency:nios2 can't see the usb-blaster

Hi!

I became very tired and i really must achieve to use nios2 processor:

I can implement my *time_limited.sof file to my de1 board but

"Nios II 9.1 Software Build Tools for Eclipse" cant see usb-blaster.

I checked my quartus project, my pin assignments and they are all ok.

And I make my quartus pin configuration:

Quartus II > Menu bar: Assignments > "Device & Pin Options" > tab : "Unused Pins" > as input tri-stated.

I would be very thankfull if you help me!!!:confused: