The Firmware Change Update feature on the BlackBerry 9780 is a robust but technical process. Unlike modern OTA (Over-The-Air) updates, it relies heavily on a PC tether and file manipulation, offering power users the ability to "Shrink" the OS to optimize the device's performance.
Try a different USB port or reinstall the BlackBerry Drivers. Update Fails Mid-Way Remove the battery, reconnect to the PC, and run Loader.exe immediately. "No Updates Found" Firmware Change Update on BLACKBERRY 9780 Bold