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Here are the steps to fix the “MMC cannot open the file virtmgmt.msc” error on Windows 10:
Turn on Hyper-V from Windows Features: If you have a shortcut to open the Hyper-V Manager, but it is not turned on on your computer, you will get this error message. The simplest way to bypass this problem is by enabling Hyper-V Hyper-V Management Tools and Hyper-V Platform from the Windows Features window. Search for “Turn Windows features on or off” in the Taskbar search box, and click the corresponding result. After opening the Windows Features window, make a tick in the Hyper-V checkbox and click the OK button. Then, your PC will go through some changes that you can see on your screen. Once done, restart your computer and try to open the shortcut to get Hyper-V on your PC.
Rename or delete the MMC folder: At times, malware can damage files and folders on your computer. If the MMC folder representing the background process has become corrupted, there is a chance of getting this error. That is why follow these steps to rename or delete this folder on your computer. First, show hidden files and folders in Windows 10 and navigate to this path- C:\Users\your-username\AppData\Roaming\Microsoft Here you will see the MMC folder. You can either rename this folder or delete it from your PC. Then, restart your computer, and try to open the Hyper-V.
Please replace “your-username” with your actual username in the path above.