8X SBC Pro "Unrecognized filesystem type" error at boot

I just acquired ConnectCore 8X SBC Pro and tried to program the yocto firmware. Followed the steps from the link : Step 3 - Program the Yocto firmware | ConnectCore 8X. SD Card and USB mass storage methods failed. Connect Core freezes right after the command “run install_linux_fw_sd” or “run install_linux_fw_usb”. After that i realized the error message at the boot up.

** Unrecognized filesystem type **

Any idea about the cause of this error? How to solve it?

Thanks in advance.