Perform a factory reset via Recovery Mode (Power + Volume Up).

| Error | Cause | Solution | | :--- | :--- | :--- | | Error 0xFC (CheckSum error) | Corrupted download or mismatched PAC file | Re-download firmware; compare MD5 checksum with source. | | Error 0x17 (USB handshake failed) | Driver conflict or bad USB port | Use USB 2.0 port; reinstall Unisoc drivers; disable Windows Defender real-time scan. | | Phone stuck in bootloop | Userdata partition not formatted | Boot into recovery (Vol Up + Power) and perform . | | Touchscreen not working | Wrong display driver in new firmware | This is a critical OEM mismatch. Revert to old firmware or contact OEM support. |

chipset, commonly found in budget-friendly Android tablets and smartphones from brands like Blackview, Teclast, Oscal, and Chuwi. Updating this firmware typically involves using the Unisoc Upgrade Tool

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