A universal serial bus (USB) input device, such as a keyboard or a mouse, may not work during the Installing Devices portion of GUI-mode Windows Setup. This behavior can prevent Setup from completing: if Setup tries to install an unsigned driver, an Unsigned Driver dialog box appears and requires user input.
This problem occurs because device installation for a USB version 1.1 companion controller of a USB version 2.0 enhanced host controller interface (EHCI) controller may not have completed by the time the unsigned driver installation occurs. When this behavior occurs, all USB 1.1 devices do not work, including mouse devices and keyboards.
To resolve this problem, use one of the following methods:
Add a driver test signature to suppress the unsigned driver dialog box. For more information about how to obtain and install a driver test signature, click the following article number to view the article in the Microsoft Knowledge Base:
Use unattended Setup to ignore the driver signing policy. For more information about how to perform unattended Setup, click the following article number to view the article in the Microsoft Knowledge Base:
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