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cmdwindows-10vmwaremountvmware-workstation

VMware Workstation and Device/Credential Guard are not compatible

I have been running VMware for the last year no problems, today I opened it up to start one of my VM and get an error message, see screen shot.

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I did follow the link and went through the steps, on step 4 I need to mount a volume using "mountvol". when I try to mount a volume using mountvol X: \\?\Volume{5593b5bd-0000-0000-0000-c0f373000000}\ it keeps saying The directory is not empty. I even created a partition with 2GB and still the same message.

My Questions:

How can I mount the volume that is not empty even though it is?

Why did this Device/Credential Guard auto enable itself and how can I get rid of it or disable it.

CMD: enter image description here

Solution

  • Device/Credential Guard is a Hyper-V based Virtual Machine/Virtual Secure Mode that hosts a secure kernel to make Windows 10 much more secure.

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    ...the VSM instance is segregated from the normal operating system functions and is protected by attempts to read information in that mode. The protections are hardware assisted, since the hypervisor is requesting the hardware treat those memory pages differently. This is the same way to two virtual machines on the same host cannot interact with each other; their memory is independent and hardware regulated to ensure each VM can only access it’s own data.

    From here, we now have a protected mode where we can run security sensitive operations. At the time of writing, we support three capabilities that can reside here: the Local Security Authority (LSA), and Code Integrity control functions in the form of Kernel Mode Code Integrity (KMCI) and the hypervisor code integrity control itself, which is called Hypervisor Code Integrity (HVCI).

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    When these capabilities are handled by Trustlets in VSM, the Host OS simply communicates with them through standard channels and capabilities inside of the OS. While this Trustlet-specific communication is allowed, having malicious code or users in the Host OS attempt to read or manipulate the data in VSM will be significantly harder than on a system without this configured, providing the security benefit.

    Running LSA in VSM, causes the LSA process itself (LSASS) to remain in the Host OS, and a special, additional instance of LSA (called LSAIso – which stands for LSA Isolated) is created. This is to allow all of the standard calls to LSA to still succeed, offering excellent legacy and backwards compatibility, even for services or capabilities that require direct communication with LSA. In this respect, you can think of the remaining LSA instance in the Host OS as a ‘proxy’ or ‘stub’ instance that simply communicates with the isolated version in prescribed ways.


    And Hyper-V and VMware didn't work the same time until 2020, when VMware used Hyper-V Platform to co-exist with Hyper-V starting with Version 15.5.5.

    How does VMware Workstation work before version 15.5.5?

    VMware Workstation traditionally has used a Virtual Machine Monitor (VMM) which operates in privileged mode requiring direct access to the CPU as well as access to the CPU’s built in virtualization support (Intel’s VT-x and AMD’s AMD-V). When a Windows host enables Virtualization Based Security (“VBS“) features, Windows adds a hypervisor layer based on Hyper-V between the hardware and Windows. Any attempt to run VMware’s traditional VMM fails because being inside Hyper-V the VMM no longer has access to the hardware’s virtualization support.

    Introducing User Level Monitor

    To fix this Hyper-V/Host VBS compatibility issue, VMware’s platform team re-architected VMware’s Hypervisor to use Microsoft’s WHP APIs. This means changing our VMM to run at user level instead of in privileged mode, as well modifying it to use the WHP APIs to manage the execution of a guest instead of using the underlying hardware directly.

    What does this mean to you?

    VMware Workstation/Player can now run when Hyper-V is enabled. You no longer have to choose between running VMware Workstation and Windows features like WSL, Device Guard and Credential Guard. When Hyper-V is enabled, ULM mode will automatically be used so you can run VMware Workstation normally. If you don’t use Hyper-V at all, VMware Workstation is smart enough to detect this and the VMM will be used.

    System Requirements

    To run Workstation/Player using the Windows Hypervisor APIs, the minimum required Windows 10 version is Windows 10 20H1 build 19041.264. VMware Workstation/Player minimum version is 15.5.5.

    To avoid the error, update your Windows 10 to Version 2004/Build 19041 (Mai 2020 Update) and use at least VMware 15.5.5.