Looking over everything that you did, it sounds like you did this correctly. Assuming there were no power issues while burning the fw/FPGA image this shouldn't cause an issue. You may want to try booting it into safe mode and trying again.
However, this forum is aimed to provide support for the NI-USRP driver and LabVIEW. Since you are using the UHD driver, you will likely get a more detailed answer by sending this question to the USRP mailing list. You should get a response fairly quickly.
SDR Product Manager National Instruments | Ettus Research