Libusb-win32-filter was not designed to run on Windows Vista, but it can be made to work. You must right click the “libusb-win32-filter-bin-0.1.12.1.exe” executable, click the Compatiblity tab, and check “Run this program in compatibility mode for”, and select Windows XP (Service Pack 2) in the list.
If you fail to do these steps, the driver will install without any complaints, but all USB devices on the computer will be rendered inoperable until you figure out how to uninstall it.
Please also be aware that the driver is unstable on Windows Vista and occasionally causes the operating system to kernel panic (blue screen of death). This happens particularly when the computer attempts to enter a low-power mode.
If you do not wish to install libusb-win32-filter on Vista (and we do not recommend you do), you may still use the ipsw tool without it.