diff --git a/setupOffice.ps1 b/setupOffice.ps1
index 13bdc93..3b01ce0 100644
--- a/setupOffice.ps1
+++ b/setupOffice.ps1
@@ -31,7 +31,7 @@ function InstallOffice {
     if (Test-Path -Path $imagePath -PathType Leaf) {
         $mountResult = Mount-DiskImage -ImagePath $imagePath -PassThru
         $driveLetter = ($mountResult | Get-Volume).DriveLetter
-        $setupPath = Join-Path $driveLetter "\Office\Setup64.exe"
+        $setupPath = Join-Path $driveLetter ":\Office\Setup64.exe"
         Write-Host "Office setup path: $setupPath"
         Start-Process -FilePath $setupPath -Wait
     } else {