Hard disk configuration for installing Windows 2012 R2 in VirtualBox without hitting the 0x80042565 error

autounattend.xml

<?xml version="1.0" encoding="utf-8"?>
<unattend xmlns="urn:schemas-microsoft-com:unattend">
  <!-- only relevant information to install Windows 2012 R2 in VirtualBox without hitting 0x80042565 error -->
    <settings pass="windowsPE">
        <component name="Microsoft-Windows-Setup" processorArchitecture="amd64" publicKeyToken="31bf3856ad364e35" language="neutral" versionScope="nonSxS" xmlns:wcm="http://schemas.microsoft.com/WMIConfig/2002/State" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
            <DiskConfiguration>
                <WillShowUI>OnError</WillShowUI>
                <Disk wcm:action="add">
                    <DiskID>0</DiskID>
                    <WillWipeDisk>true</WillWipeDisk>
					<CreatePartitions>
						<!--  Windows RE Tools partition  -->
						<CreatePartition wcm:action="add">
							<Order>1</Order>
							<Type>Primary</Type>
							<!-- Size is important. By default, Windows 2012 R2 uses a partition size of 350 MByte and *not* 300 MByte as shown in the examples -->
							<Size>350</Size>
						</CreatePartition>
						<!--  Windows partition  -->
						<CreatePartition wcm:action="add">
							<Order>2</Order>
							<Type>Primary</Type>
							<!-- Use the the available space of the hard disk -->
							<Extend>true</Extend>
						</CreatePartition>
					</CreatePartitions>
					<ModifyPartitions>
						<!--  Windows RE Tools partition. This partition is required and must have a size of at least 350 MByte.   -->
						<!-- partitions smaller than 350 MByte results in an 0x80042565 error -->
						<ModifyPartition wcm:action="add">
							<Order>1</Order>
							<PartitionID>1</PartitionID>
							<Label>WinRE</Label>
							<Format>NTFS</Format>
							<!-- <TypeID>de94bba4-06d1-4d40-a16a-bfd50179d6ac</TypeID> -->
						</ModifyPartition>
						<!--  Windows partition  -->
						<ModifyPartition wcm:action="add">
							<Order>2</Order>
							<PartitionID>2</PartitionID>
							<Active>true</Active>
							<Label>Windows</Label>
							<Letter>C</Letter>
							<Format>NTFS</Format>
						</ModifyPartition>
					</ModifyPartitions>
                </Disk>
            </DiskConfiguration>
            <ImageInstall>
                <OSImage>
                    <InstallFrom>
                        <MetaData wcm:action="add">
                            <Key>/IMAGE/INDEX</Key>
							<!-- Extract .iso to get the index or name from install.wim -->
							<!-- Powershell: dism /get-wiminfo /wimfile:install.wim -->
							<!-- 2 = Windows Server 2012 R2 SERVERSTANDARD -->
                            <Value>2</Value>
                        </MetaData>
                    </InstallFrom>
                    <WillShowUI>OnError</WillShowUI>
					<!-- using "true" does not work b/c Windows tries to install to the WinRE partition -->
                    <InstallToAvailablePartition>false</InstallToAvailablePartition>
                    <InstallTo>
                        <DiskID>0</DiskID>
                        <PartitionID>2</PartitionID>
                    </InstallTo> 
				        </OSImage>
            </ImageInstall>
            <UserData>
                <AcceptEula>true</AcceptEula>
            </UserData>
        </component>
    </settings>
</unattend>

CAN U EXPLAIN HOW TO USE THIS FILE ?