Middle mouse button doesn't work

My middle mouse button doesn’t work only in blender. i tried to configure on the user preferences and it still doesn’t work. is there any other way to rotate the view around the 3D model?

Alt+left click(hold)=pan
Alt+shift+left click(hold)=strafe
Alt+ctrl+left click(hold)=zoom
under file-user preferences-input there has to be -emulate 3 button mouse- enabled

Thank you!