Click . The progress bar will turn yellow, then green upon completion. ⚠️ Important Safety Tips
Hold down the dedicated boot key combination on the phone (typically the or Key 1 + Key 3 depending on the specific hardware revision) while inserting the USB cable from the PC. If the flashing process doesn't begin immediately, a
If the flashing process doesn't begin immediately, a common trick is to , then unplug the USB cable and plug it back in while still holding them. The software should then detect the phone and start. Wait patiently for the process to complete, which can take 10-15 minutes. Many "scraped" firmware files found on generic file-hosting
Many "scraped" firmware files found on generic file-hosting sites suffer from bit rot or corrupted sectors. If you attempt to flash a C3520 with a corrupted loader, you risk permanent hardware failure. you risk permanent hardware failure.