Fix Oppo A31 CPH2015 Download Not Completed Error (Oppo_Custom.bin)

If you’re flashing Oppo A31 CPH2015 and facing the dreaded “Download not completed” error, don’t panic — this guide explains exactly why it happens and how to fix it using the Oppo_Custom.bin file. This issue commonly appears during firmware flashing on MTK devices using tools like SP Flash Tool, DownloadTool, or MSMDownloadTool.

Why the Error Happens

The “Download not completed” message usually occurs due to one of the following reasons:

• Missing or corrupted Oppo_Custom.bin file in the firmware package
• Incompatible firmware region or build version
• Damaged or mismatched scatter file during flashing
• DA/Authentication file not matching the phone’s security policy
• Interruption during flashing (loose cable or low battery)

This is a common issue on MTK-based Oppo devices, especially the CPH2015 variant of Oppo A31.

Tools & Files Required

Before starting, make sure you have:

• SP Flash Tool or DownloadTool (latest version)
• MTK USB Drivers properly installed on your PC
• Oppo A31 CPH2015 firmware (official stock ROM)
• Oppo_Custom.bin file (download from MobiFirms.com)
• A good quality USB cable and a charged phone

Step-by-Step Solution

Step 1: Extract the Firmware

Unzip your downloaded Oppo A31 firmware package on your desktop. Check if it contains the file Oppo_Custom.bin inside the main folder.

Step 2: Add Oppo_Custom.bin Manually

If missing, download Oppo_Custom.bin separately from MobiFirms.com → Oppo → A31 CPH2015 Fixed Firmware Section.
Place it in the same directory as your firmware scatter file.

Step 3: Load Firmware in Flash Tool

• Open SP Flash Tool.
• Load the scatter.txt file from your firmware folder.
• Make sure Oppo_Custom.bin is listed and checked.
• Select Download Only mode.

Step 4: Connect and Flash

• Power off the phone completely.
• Connect to PC while holding Volume Up or Down.
• Wait for flashing to complete successfully.

Step 5: Reboot Device

Once flashing finishes, disconnect and power on the phone. The “Download not completed” error should now be fixed.

Pro Tips from Technicians

• Always use official firmware that matches your device’s region code (CPH2015EX or CPH2015).
• For repeated flashing errors, use Format + Download mode (only if you have full firmware including secro.img and nvram).
• Never rename Oppo_Custom.bin — it must match the firmware’s naming pattern.
• Backup your IMEI using MauiMeta or UFI Box before flashing.

Final Words

Fixing the Oppo A31 CPH2015 Download not completed error is simple once you replace or restore the Oppo_Custom.bin file correctly. Always download 100% tested files from trusted sources like MobiFirms.com to avoid firmware corruption or flashing failure.

👉 Download Oppo_Custom.bin for Oppo A31 CPH2015 now from MobiFirms.com and fix your phone today!