Flashing:
Phoenix_[Version]_[Build Number]_[Region].rpkg
If you are trying to flash a real Nokia X7-00 (Symbian) or the newer Nokia X7 (Android 8.1 / Nokia 8.1), the process is different:
It is crucial to download the correct firmware for your specific variant (TA-1119, TA-1121, TA-1128, TA-1131).
Flashing a stock ROM carries inherent risks. You must configure your workstation correctly before attempting the process:
What are you seeing if the installation fails? Is your phone's bootloader locked or unlocked ?