How would I get past the digital signature error when modifying Hyper-V UEFI firmware in vmchipset?

Discussion in 'BIOS Mods' started by AS91092, May 17, 2020.

  1. AS91092

    AS91092 MDL Novice

    Sep 3, 2018

    I'm trying to modify vmchipset.dll and make it use a modified Hyper-V UEFI firmware. (VMFW resource 13505, Host is Windows 10 Enterprise LTSC) When I make the modification and place it in \Windows\System32, whenever I go to start any virtual machine I end up getting a couldn't verify digital signature error (HRESULT 0x80070241). the vmwp refuses to start. from initial debugging it looks like it's an assert of sorts.

    Anyone know what's going on and if there's any way to bypass the signature check?
  2. NyaMisty

    NyaMisty MDL Novice

    Jun 4, 2020
    Under HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Virtualization, add reg value "RelaxWorkerSigning" with type REG_DWORD, content 1, and then goto "Image File Execution Options"(Google it), delete the vmwp.exe and vmcompute.exe. Then everything's done