Encountering the (often displayed as _BFK_NV_W Failed: NV data in device is crashed or Nv_WLTE Failed ) in the Spreadtrum (SPD) Flash Tool is a common yet frustrating issue for users trying to flash firmware on Spreadtrum-powered devices. This error typically signifies a corruption or mismatch in the Non-Volatile (NV) RAM partition, which holds critical calibration data, IMEI, and network settings.
If you fix the error by skipping NV partitions, your phone might have a 0000... IMEI and no network. Be prepared to restore the IMEI.
If the NVRAM partition is severely corrupted, you may need to erase it before flashing.
(Backup NV) error in the Spreadtrum (SPD) Flash Tool typically occurs because the tool is trying to back up or write to the device's Non-Volatile (NV) memory—which contains critical calibration and IMEI data—and failing due to a mismatch or corrupted partition. Common Fixes Disable NV Backup SPD Upgrade or Research Download Tool (gear icon) > spd flash tool bkf nv error
Ensure the firmware .pac file you are attempting to flash matches your exact device model and build number. Flashing the wrong variant frequently corrupts the NV data.
You will see a table listing all image files contained inside the .pac archive (e.g., boot.img , system.img , userdata.img ).
Avoids data packet drops common with USB 3.0 ports and SPD tools. Encountering the (often displayed as _BFK_NV_W Failed: NV
If you are facing this error during firmware upgrades or downgrades, this guide provides a comprehensive overview of causes and tested solutions to fix your device. What is the SPD Flash Tool BKF NV Error?
Look at the list of files under the backup strategy. Locate items related to , PhaseCheck , and ProdNV .
Alternative: Use a tool like to perform a factory reset and wipe NVRAM before flashing. Method 3: Using SPD Research Tool (For Advanced Users) IMEI and no network
If you downloaded an "Ota" package or an incomplete firmware file, locate and download a . What to Do If You Lose Your IMEI (No Network Signal)
Download the meant for your specific build number. Re-flash using the latest SPD Upgrade Download Tool. Method 2: Clearing NVRAM/Factory Reset
SPD distributes two tools:
Before flashing any MediaTek device, always perform a "Read Back" of the entire NVRAM region (address 0x[Your NVRAM Start] to size 0x500000 ). This 5MB backup can save your phone if you see the BKF NV Error.