MS Store Installer - Download latest if cached files out of date

The Microsoft Store installer script now will check whether the cached files are up to date before using them, and if not it will download the latest and warn the user to update the cache.

Also added ForceCachedFilesOnly and NoCheckLatestVersion to control this behavior. ForceCachedFilesOnly still checks and warns the user about a newer version but still uses the cache, while NoCheckLatestVersion uses the cache without even checking.

Installer Scripts/Install-Microsoft-Store.ps1

@@ -4,7 +4,7 @@
 
 # Author: ThioJoe
 # Repo Url: https://github.com/ThioJoe/Windows-Sandbox-Tools
-# Last Updated: April 16, 2026
+# Last Updated: April 24, 2026
 
 param(
     # Optional switch to output the generated XML files to the working directory
@@ -16,11 +16,17 @@ param(
     # Optional switch to skip the download and install, but still show the packages found 
     [switch]$noDownload,
 
-    # Optional path to a local directory containing the installation files. If provided, the download steps will be skipped.
+    # Optional path to a local directory containing the installation files. If provided, the download steps will be skipped if the cached files are up to date.
     #   - Just copy the entire "MSStore Install" folder with the files the script normally downloads, and put it in your mounted folder to avoid having to re-download it.
     #        - You can find the "MSStore Install" folder in the "Downloads" folder.
     #   - Make sure to use the mounted path from the perspective of within the sandbox.
-    [string]$ExistingInstallerFilesPath
+    [string]$ExistingInstallerFilesPath,
+
+    # If set, forces using the installer files from ExistingInstallerFilesPath even if a new version exists. Still warns about there being a new version.
+    [switch]$ForceCachedFilesOnly,
+
+    # If set, implies ForceCachedFilesOnly and uses cached installer files only, but does not even bother checking for a latest version.
+    [switch]$NoCheckLatestVersion
 )
 
 # --- Parameter Usage Examples ---
@@ -38,6 +44,16 @@ param(
 
 # =======================================================
 
+# Validate parameter combinations
+if ($NoCheckLatestVersion) {
+    $ForceCachedFilesOnly = [switch]::new($true)
+}
+if ($ForceCachedFilesOnly -and [string]::IsNullOrWhiteSpace($ExistingInstallerFilesPath)) {
+    Write-Host "Error: -ForceCachedFilesOnly requires -ExistingInstallerFilesPath to be specified." -ForegroundColor Red
+    Read-Host "Press Enter to exit"
+    exit 1
+}
+
 # --- Configuration ---
 # Note: These defaults should work for the regular current build of Microsoft Store, but I haven't tested using any of the other values. So fetching insider builds of MS Store (if any) might not work.
 $flightRing = "Retail"             # Apparently accepts 'Retail', 'Internal', and 'External'
@@ -74,26 +90,22 @@ $subfolderName = "MSStore Install"
 # Category ID for the Microsoft Store app package
 $storeCategoryId = "64293252-5926-453c-9494-2d4021f1c78d" 
 
+# Set up the default download directory
+$workingDir = Join-Path -Path $userDownloadsFolder -ChildPath $subfolderName
+$pauseAtEnd = $false
+
 if ($ExistingInstallerFilesPath) {
-    if (Test-Path -Path $ExistingInstallerFilesPath) {
+    if (-not (Test-Path -Path $ExistingInstallerFilesPath)) {
-        $workingDir = $ExistingInstallerFilesPath
-        Write-Host "Using local source path: $workingDir" -ForegroundColor Yellow
-    } else {
         Write-Error "The specified local source path does not exist: $ExistingInstallerFilesPath"
         return
     }
-} else {
-    # Combine them to create the full working directory path
-    $workingDir = Join-Path -Path $userDownloadsFolder -ChildPath $subfolderName
-    
-    # Create the directory if it doesn't exist
-    if (-not (Test-Path -Path $workingDir)) {
-        New-Item -Path $workingDir -ItemType Directory -Force | Out-Null
-    }
 }
 
 If ($debugSaveFiles) {
-    Write-Host "All files (logs, downloads) will be saved to: '$workingDir'" -ForegroundColor Yellow
+    if (-not (Test-Path -Path $workingDir)) {
+        New-Item -Path $workingDir -ItemType Directory -Force | Out-Null
+    }
+    Write-Host "All new files (logs, downloads) will be saved to: '$workingDir'" -ForegroundColor Yellow
 }
 
 # --- XML Templates ---
@@ -221,7 +233,7 @@ $headers = @{ "Content-Type" = "application/soap+xml; charset=utf-8" }
 $baseUri = "https://fe3.delivery.mp.microsoft.com/ClientWebService/client.asmx"
 
 try {
-    if (-not $ExistingInstallerFilesPath) {
+    if (-not $NoCheckLatestVersion) {
         # Step 1: Get Cookie
         Write-Host "Step 1: Getting authentication cookie..."
         $cookieRequestPayload = $cookieXmlTemplate
@@ -366,61 +378,106 @@ try {
             Write-Host "Total files to download: $($packagesToDownload.Count)" -ForegroundColor Cyan
             Write-Host "------------------------------------------------------------"
 
+            # --- Check Cache ---
+            $useExistingFiles = $false
+            $updateDetected = $false
+
+            if ($ExistingInstallerFilesPath) {
+                $allCached = $true
+                foreach ($package in $packagesToDownload) {
+                    $fileExtension = [System.IO.Path]::GetExtension($package.FileName)
+                    $expectedFile = Join-Path $ExistingInstallerFilesPath "$($package.FullName)$($fileExtension)"
+                    if (-not (Test-Path $expectedFile)) {
+                        $allCached = $false
+                        break
+                    }
+                }
+
+                if ($allCached) {
+                    Write-Host "Cached files are up to date. Using local source path: $ExistingInstallerFilesPath" -ForegroundColor Green
+                    $useExistingFiles = $true
+                    $workingDir = $ExistingInstallerFilesPath
+                } elseif ($ForceCachedFilesOnly) {
+                    Write-Host "WARNING: Cached files are out of date or missing, but using cache anyway (-ForceCachedFilesOnly)." -ForegroundColor Yellow
+                    Write-Host "Please update your cache at: $ExistingInstallerFilesPath" -ForegroundColor Yellow
+                    $useExistingFiles = $true
+                    $workingDir = $ExistingInstallerFilesPath
+                    $updateDetected = $true
+                    $pauseAtEnd = $true
+                } else {
+                    Write-Host "Newer versions detected or cached files missing. Cache is out of date." -ForegroundColor Yellow
+                    $updateDetected = $true
+                    $pauseAtEnd = $true
+                }
+            }
+
 
             # --- Loop through the filtered list, get URLs, and download ---
-            Write-Host "Step 4: Fetching URLs and downloading files..." -ForegroundColor Magenta
+            if (-not $useExistingFiles) {
-
+                if (-not (Test-Path -Path $workingDir)) {
-            $originalPref = $ProgressPreference
+                    New-Item -Path $workingDir -ItemType Directory -Force | Out-Null
-            $ProgressPreference = 'SilentlyContinue'
-            
-            foreach ($package in $packagesToDownload) {
-                Write-Host "Processing: $($package.FullName)"
-
-                # Get the download URL for this specific package
-                $fileUrlRequestPayload = $fileUrlXmlTemplate -f $encryptedCookieData, $package.UpdateID, $package.RevisionNumber, $currentBranch, $flightRing, $flightingBranchName
-                $fileUrlResponse = Invoke-WebRequest -Uri "$baseUri/secured" -Method Post -Body $fileUrlRequestPayload -Headers $headers -UseBasicParsing
-                $fileUrlResponseXml = [xml]$fileUrlResponse.Content
-
-                $fileLocations = $fileUrlResponseXml.Envelope.Body.GetExtendedUpdateInfo2Response.GetExtendedUpdateInfo2Result.FileLocations.FileLocation
-                $baseFileName = [System.IO.Path]::GetFileNameWithoutExtension($package.FileName)
-                $downloadUrl = ($fileLocations | Where-Object { $_.Url -like "*$baseFileName*" }).Url
-
-                if (-not $downloadUrl) {
-                    Write-Warning "  -> Could not retrieve download URL for $($package.FileName). Skipping."
-                    continue
-                }
-                if ($noDownload) {
-                    Write-Host "  -> Skipping download for $($package.FullName) because of -noDownload switch." -ForegroundColor Yellow
-                    continue
                 }
 
-                # Download the file
+                Write-Host "Step 4: Fetching URLs and downloading files..." -ForegroundColor Magenta
-                # Construct a more descriptive filename using the package's full name and its original extension
+
-                $fileExtension = [System.IO.Path]::GetExtension($package.FileName)
+                $originalPref = $ProgressPreference
-                $newFileName = "$($package.FullName)$($fileExtension)"
+                $ProgressPreference = 'SilentlyContinue'
-                $filePath = Join-Path $workingDir $newFileName
                 
-                Write-Host "  -> Downloading from: $downloadUrl" -ForegroundColor Gray
+                foreach ($package in $packagesToDownload) {
-                Write-Host "  -> Saving to: $filePath"
+                    Write-Host "Processing: $($package.FullName)"
 
-                try {
+                    # Get the download URL for this specific package
-                    Invoke-WebRequest -Uri $downloadUrl -OutFile $filePath -UseBasicParsing
+                    $fileUrlRequestPayload = $fileUrlXmlTemplate -f $encryptedCookieData, $package.UpdateID, $package.RevisionNumber, $currentBranch, $flightRing, $flightingBranchName
-                    Write-Host "  -> SUCCESS: Download complete." -ForegroundColor Green
+                    $fileUrlResponse = Invoke-WebRequest -Uri "$baseUri/secured" -Method Post -Body $fileUrlRequestPayload -Headers $headers -UseBasicParsing
-                } catch {
+                    $fileUrlResponseXml = [xml]$fileUrlResponse.Content
-                    Write-Error "  -> FAILED to download $($newFileName). Error: $($_.Exception.Message)"
+
+                    $fileLocations = $fileUrlResponseXml.Envelope.Body.GetExtendedUpdateInfo2Response.GetExtendedUpdateInfo2Result.FileLocations.FileLocation
+                    $baseFileName = [System.IO.Path]::GetFileNameWithoutExtension($package.FileName)
+                    $downloadUrl = ($fileLocations | Where-Object { $_.Url -like "*$baseFileName*" }).Url
+
+                    if (-not $downloadUrl) {
+                        Write-Warning "  -> Could not retrieve download URL for $($package.FileName). Skipping."
+                        continue
+                    }
+                    if ($noDownload) {
+                        Write-Host "  -> Skipping download for $($package.FullName) because of -noDownload switch." -ForegroundColor Yellow
+                        continue
+                    }
+
+                    # Download the file
+                    # Construct a more descriptive filename using the package's full name and its original extension
+                    $fileExtension = [System.IO.Path]::GetExtension($package.FileName)
+                    $newFileName = "$($package.FullName)$($fileExtension)"
+                    $filePath = Join-Path $workingDir $newFileName
+                    
+                    Write-Host "  -> Downloading from: $downloadUrl" -ForegroundColor Gray
+                    Write-Host "  -> Saving to: $filePath"
+
+                    try {
+                        Invoke-WebRequest -Uri $downloadUrl -OutFile $filePath -UseBasicParsing
+                        Write-Host "  -> SUCCESS: Download complete." -ForegroundColor Green
+                    } catch {
+                        Write-Error "  -> FAILED to download $($newFileName). Error: $($_.Exception.Message)"
+                    }
+                    Write-Host ""
                 }
-                Write-Host ""
+                
-            }
+                $ProgressPreference = $originalPref
-            
-            $ProgressPreference = $originalPref
 
-            Write-Host "------------------------------------------------------------"
+                Write-Host "------------------------------------------------------------"
-            Write-Host "Finished downloading packages to: $workingDir" -ForegroundColor Green
+                Write-Host "Finished downloading packages to: $workingDir" -ForegroundColor Green
+            } else {
+                Write-Host "Step 4: Skipping download step (Using existing cached files)." -ForegroundColor Cyan
+                Write-Host "------------------------------------------------------------"
+            }
 
         } catch {
             Write-Host "An error occurred during the filtering or downloading phase:" -ForegroundColor Red
             Write-Host $_.Exception.ToString()
         }
+    } else {
+        $workingDir = $ExistingInstallerFilesPath
+        Write-Host "Skipping update checks (-NoCheckLatestVersion). Using existing files from: $workingDir" -ForegroundColor Cyan
     }
 
     If ($noDownload) {
@@ -550,3 +607,12 @@ try {
         Write-Host $_.Exception.ToString()
     }
 }
+
+if ($updateDetected) {
+    Write-Host "`nACTION REQUIRED: Newer file versions were downloaded." -ForegroundColor Yellow
+    Write-Host "Please update your cache at: $ExistingInstallerFilesPath" -ForegroundColor Yellow
+}
+
+if ($pauseAtEnd) {
+    Read-Host "`nPress Enter to exit"
+}