Windows 11 requires that all kernel-mode drivers be digitally signed by Microsoft. Most Virtual USB Multikey drivers were developed years ago and either have no signature or use test signatures that Windows 11 rejects.
Windows 11 requires all kernel-mode drivers to be digitally signed by a trusted certificate authority. The Virtual USB Multikey is an open-source or third-party solution that typically lacks this expensive Microsoft certification. Consequently, Windows 11 will block the driver installation by default to protect the system from malware. Virtual Usb Multikey Driver Windows 11
If the driver is but not working:
: This is almost always caused by Memory Integrity being enabled. Missing from Device Manager Windows 11 requires that all kernel-mode drivers be
You have two options: