I tried today on an ASUSPRO P2540UA system with Windows 10 64-bit, version 1903 and receive the same error message. I know for sure that I got the Intel ME firmware update on a 64-bit Windows 10, version 1809. I think the problem is in the latest version of Windows 10 (1903). I also tried with Windows Defender / SmartScreen disabled all without success. Has anyone managed the firmware update on the 1903 version?
I must admit that I may have been mistaken. I also tried on a Dell system with Windows 10 64-bit, version 1903. Intel ME System Tools v7 r2 -> FWUpdate -> WIN32:
1
FWUpdLcl.exe -SAVE old.bin
and it worked. Can there be another restriction set by the manufacturer?