Installing MultiKey 18.1 is complex because it involves unsigned drivers that modern Windows versions often block.
MultiKey 18.1 x64 is engineered specifically for 64-bit Windows operating systems (Windows 7, 8, 10, and 11). Multikey 18.1 X64
"Multikey 18.1 X64" most likely refers to a virtual USB dongle emulator Installing MultiKey 18
The installation of MultiKey 18.1 x64 generally requires disabling Windows Driver Signature Enforcement. Modern 64-bit Windows systems require all kernel drivers to be digitally signed by a trusted certificate. MultiKey is usually unsigned (or uses a test-signing certificate), requiring the user to enter "Test Mode" or disable signature enforcement via the boot menu. Multikey 18.1 X64