| Error | Solution | |-------|----------| | STATUS_SEC_AUTH_FILE_NEEDED | Use MTK Bypass Utility v27+ | | S_BROM_DOWNLOAD_DA_FAIL | Reinstall VCOM drivers, change USB port | | PMT changed for the ROM | In SP Flash Tool → choose “Format all + download” (risky) | | Phone not detected | Try different cable, disable USB selective suspend | | Stuck at 100% | Wait 10 min, then reflash without preloader |

You can verify if your firmware is genuine by checking the Serial Number in Settings > About Device and comparing it with the original packaging. How to Install or Restore Firmware If you have a refurbished

In these cases, take your refurbished OPPO A78 to an authorized OPPO service center. For a small fee, they will flash the using their licensed OPPO Flash Tool. This is the only 100% safe method.

If you have purchased an Oppo A78 running refurbished firmware:

Before attempting to install or "re-flash" firmware, thorough preparation is mandatory to avoid permanent damage.