If you use [Oracle VirtualBox](https://www.virtualbox.org/) on a Windows host machine you will probably already be aware that Hyper-V (Microsoft's equivalent virtual machine software) prevents VirtualBox from using the hardware virtualization features of your system. The hardware virtualization features will be called either VT-x or AMD-V depending on your CPU. 

If you don't  use Microsoft Hyper-V you can disable it:

![Turn Windows features on or off](https://cdn.steemitimages.com/DQmfY3uy6cUbvgmmcX4bJjGEfgqezdMuHHSzGjPVJbYPiWz/2018-08-05_123105.png)
* Open the  **Turn Windows feautres on or off**  application 
* Uncheck the Hyper-V item and it's sub-items
* Restart the device

Since April 2018 Windows 10 now includes security features called **Core Isolation** and **Memory Integrity** which use virtualization technology to keep important system processes separate from other processes, a technique is often referred to as  [sandboxing](https://techterms.com/definition/sandboxing).
The benefit of having **Memory Integrity** active is that a malicious program will be unlikely to gain access to memory used by the protected processes. 
The unfortunate side effect of using the **Memory integrity** feature is that VirtualBox (and other third party virtual machine software) will be unable to use VT-x or AMD-V features. 
If you upgraded to the April 2018 version of Windows 10 the **Memory Integrity** feature is probably disabled but new installations and future updates are likely to enable it by default, I encountered the problem while testing a [Windows Insider](https://insider.windows.com) preview version.  

Take a look at this [How-to-Geek article](https://www.howtogeek.com/357757/what-are-core-isolation-and-memory-integrity-in-windows-10/) for a detailed description of the features.

If you need to switch off the **Memory Integrity** feature:

![Turn off the Memory Integrity feature](https://cdn.steemitimages.com/DQmVv2KGdT3gXuzt4uCDJhwHZ4s8PKzAzd2g7zSAT7boUwA/2018-08-05_131839.png)
* Open **Windows Security** (formerly Windows Defender)
* Open the **Device Security** section
* Click/tap the **Core isolation details** link
* Turn off the **Memory Integrity** toggle switch
* Restart the device when prompted (the setting change may not be applied if you decline to restart when prompted)

With **Memory Integrity** and Hyper-V disabled you should be free to run Virtual Machines with full hardware acceleration support in VirtualBox.