If drivers fail to install, you may need to disable driver signature enforcement in Windows.

: For flashing, use a high-quality micro-USB cable and ensure the phone is powered off before connecting it to trigger the MTK VCOM port.

The Ultimate Guide to Nokia RM-1187 Drivers: Installation, Connectivity, and Troubleshooting

If you can tell me the you are using (e.g., Windows 10, Windows 11) or the exact error message you are receiving in Device Manager, I can give you more tailored troubleshooting steps. Share public link