Create-and-attach-VHD-OST.ps1

## USER VARIABLES Start ##
$vhdSharePath = "\\DOMAIN\DFSRoot$\OSTVHD" ## Path to VHD Store

## USER VARIABLES End ##

## GLOBAL VARIABLES Start ##
$userName = $env:USERNAME
$userDomain = $env:USERDOMAIN
$secUser = New-Object System.Security.Principal.NTAccount($userName)
$userSID = $secUser.Translate([System.Security.Principal.SecurityIdentifier])
$vhdFileName = $userName + "_EMCache.vhd"
$vhdUserDirectoryName = $userName + "_" + $userSID
$vhdDirectoryPath = $vhdSharePath + "\" + $vhdUserDirectoryName
$vhdPath = $vhdDirectoryPath + "\" + $vhdFileName
$workingDir = $env:USERPROFILE + "\AppData\Local\Temp\VHDCache"
$filesystemlabel = $userName + "_EMcache"
$outlookDir = $env:USERPROFILE + "\AppData\Local\Microsoft\Outlook"
$newWorkingDir = $workingDir + "\VHD"

## GLOBAL VARIABLES End ##

## Check if disk exsits or else create VHD
$user = $userName

    if($user -ne "") {
    Write-Host "Processing user" $user -ForegroundColor Cyan

    try
    {
        $secUser = New-Object System.Security.Principal.NTAccount($user)
        $SID = $secUser.Translate([System.Security.Principal.SecurityIdentifier])
        $diskName = "\${user}_EMCache.vhd"
        $folderName = "${User}_${SID}"
        $shareFolder = "$vhdSharePath\${folderName}"
        $diskPath = "${shareFolder}${diskName}"
        $testdiskpath = test-path $diskPath

        if(!$testdiskpath)
        {
            # Create the directory and set Allow and Full Control permissions
            if(-not (Test-Path $shareFolder))
            {
                try
                {
                    # Create the directory for the user
                    Write-Host "Creating directory ${shareFolder}"
                    New-Item -Path $shareFolder -Type Directory -Force | Out-Null

                    # Set permissions on the user folder
                    $acl = Get-Acl $shareFolder
                    $ar = New-Object System.Security.AccessControl.FileSystemAccessRule($user,"FullControl","ContainerInherit,ObjectInherit","InheritOnly","Allow")
                    $acl.SetAccessRule($ar)
                    Set-Acl $shareFolder $acl
                }
                catch
                {
                    Write-Warning "_Error: $($_.exception.message)"
                    "${user}_Error: $($_.exception.message)" | Add-Content $failedFolder
                }
            }
            else
            {
                Write-Warning "Directory for $user already exists - skipping"
            }

# Build command used for DiskPart
$maximum = "51200"  # Expands to a maximum of 30GB
$type = "expandable"
$label = "$User"+"_EMCache"

$command = @"
create vdisk file=$diskPath maximum=$maximum type=$type
select vdisk file=$diskPath
attach vdisk
create partition primary
format fs=ntfs label="$label" quick
detach vdisk
exit
"@
            # Create the user VHD via DiskPart
            Write-Host "Creating Virtual Disk"
            $command | DiskPart | Where-Object { $_.Length -gt 0 } | Out-Null
            Write-Host "Created Virtual Disk"
        }
        else
        {
            Write-Warning "EMCache path for $user already exists - skipping"
        }
    }
    catch
    {
        # Output any errors to the failed.txt file
         Write-Warning "Error processing ${user}: $($_.exception.message)"
        "${user}_Error: $($_.exception.message)" | Add-Content $failedFolder
    }
  }

## Check VHD exit ##

## ATTACH VHD Start ##
[string]$label = ""

"Attaching existing VHD"

$cmd = @"
Select vdisk file=$vhdPath
attach vdisk
exit
"@

    $cmd | diskpart | Out-Null

    $vol = Get-WMIObject -Class Win32_Volume -Filter "Label='$filesystemlabel'"
    $label = $vol.Label


"Attach VHD to system - complete"

## ATTACH VHD End ##


## READING VOLUME INFORMATION Start ##

"Reading volume information"

$link = $vol.DeviceID

"Reading volume information - complete"

## READING VOLUME INFORMATION End ##


## REMOVING DRIVE LETTER Start ##

"Removing drive letter if present"
Set-WmiInstance -input $vol -Arguments @{DriveLetter=$null} | out-null
"Removing drive letter if present - Complete"

## REMOVING DRIVE LETTER End ##


## SETTING ROOT PERMISSIONS ON DISK Start ##

"Setting root permissions on disk"

icacls.exe "$link" /grant "$varUserdomain\${varUsername}:(OI)(CI)(F)" | Out-Null

"Setting root permissions on disk - complete"

## SETTING ROOT PERMISSIONS ON DISK End ##


## MOUNTING Start ##

"Mounting"
$mountPath = Join-Path -Path $workingDir -ChildPath VHD

New-item -path $mountPath -itemtype "Directory" -ErrorAction SilentlyContinue |Out-Null

mountvol.exe $mountPath $link | Out-Null

"Mounting - complete"
## MOUNTING End ##

## DELETE RECYCLE BIN Start ##
"Delete recycle bin"

$recycleDir = "$mountPath\`$RECYCLE.BIN"

if(Test-Path $recycleDir)
{
Remove-Item -Path $recycleDir -Force -Recurse
}

"Delete recycle bin - Complete"
## DELETE RECYCLE BIN End ##

## CREATE FOLDERS IN VHD Start ##
"Create Outlook directory"

if(Test-Path -Path $outlookDir){
    Write-Host "Local Outlook Directory found" -ForegroundColor Green
    $copyLocalOutlookData = Copy-Item -Path $outlookDir -Destination $newWorkingDir -Recurse -Force

    if($copyLocalOutlookData){
        Write-Host "Local outlook data is copied!" -ForegroundColor Green
    } else {
        Write-Host "Copy local outlook data failed!" -ForegroundColor Red
        #exit 1
    }

    $removeLocalOutlookData = Remove-Item -Path $outlookDir -Recurse -Force

    if($removeLocalOutlookData){
        Write-Host "Local outlook data is removed!" -ForegroundColor Green
    }

} else {
    Write-Host "Local Outlook Directory doesn't exist or is removed already!" -ForegroundColor Yellow
}

$testworkingdir = Test-Path "$workingDir\VHD\Outlook"

if (!$testworkingdir){
New-Item -Path $workingDir\VHD\Outlook -ItemType Directory |out-null
}
"Create Outlook directory - Complete"
## CREATE FOLDERS IN VHD End ##

## CREATE JUNCTION Start ##
"Create Junction"
New-Item -ItemType SymbolicLink -Path $outlookDir -Value $workingDir\VHD\Outlook | Out-Null
"Junction created!"
## CREATE JUNCTION End ##