| Error | Cause | Solution | |-------|-------|----------| | "Failed to open USB port" | Another BlackBerry software is running (Link, Desktop Mgr) | Kill all BlackBerry processes in Task Manager. | | Device shows red LED only | Battery too low or corrupted bootROM | Leave the device on a wall charger for 2 hours, then retry. | | Autoloader crashes at 10% | Bad USB cable or USB 3.0 port | Use a USB 2.0 port. Switch to a short, thick cable. | | "Device not in engineering mode" | Wrong key combination | Attempt the 'Shift' method again. Alternatively, try the 'R' key (for "reload"). |
The BlackBerry 9790 received its final official OS from carriers worldwide. The most stable and widely recommended versions are: blackberry 9790 autoloader download