AppxBackup PowerShell Module v2.0.2

Windows Application Package Backup & Restoration Toolkit

Version: 2.0.2
Release Date: Febuary 13, 2026
PowerShell: 5.1+ (7.5+ Recommended)

Overview

AppxBackup is a complete 2026 rewrite of the 2016 original APPX backup script, transformed into a production-grade PowerShell module. This toolkit provides end-to-end Windows Store/MSIX application backup and restoration.

Key Capabilities

Complete Backup-to-Installation Pipeline - One-command backup, one-command restore
Automatic Certificate Management - Self-signed cert creation and system trust
Native Windows SDK Integration - MakeAppx and SignTool automation with tool-specific optimization
Modern MSIX Support - Full support for MSIX + legacy APPX formats
Externalized Configuration - Configuration values in JSON for easy customization

System Requirements

Minimum Requirements

PowerShell: 5.1+
OS: Windows 10 1809 / Windows Server 2019
Windows SDK: 10.0.19041.0+ (includes MakeAppx, SignTool)
Disk Space: 100 MB temporary storage
Memory: 512 MB available RAM

Recommended Configuration

PowerShell: 7.5+
OS: Windows 11 24H2 / Windows Server 2022
Windows SDK: 10.0.26100.0+ (includes MakeAppx, SignTool)
Disk Space: 1 GB+ for large packages
Memory: 2 GB+ available RAM

Administrator Privileges

Required for:

Installing certificates to LocalMachine store
Accessing WindowsApps folder on some systems

Not required for:

Basic backup operations (CurrentUser cert store)
Package creation
Most module functions

Installation

Quick Start (Developer Mode)

# 1. Clone or extract the module
cd "C:\Path\To\AppxBackup.Module"

# 2. Import the module
.\Import-AppxBackup.ps1

# 3. Verify installation
Get-Command -Module AppxBackup

Production Installation

# Install to PowerShell Modules directory
$modulePath = "$env:USERPROFILE\Documents\PowerShell\Modules\AppxBackup"
Copy-Item -Path ".\AppxBackup.Module" -Destination $modulePath -Recurse -Force

# Import globally
Import-Module AppxBackup -Force

# Verify
Get-Module AppxBackup

Workflow Example

For more detailed workflow examples, see Common Workflows in Examples/UsageExamples.md.

Scenario: Backup and Restore WorkMate App

Step 1: Backup the Application

# Find the installed app
$app = Get-AppxPackage -Name "*WorkMate*"

# Create complete backup (package + certificate)
Backup-AppxPackage -PackagePath $app.InstallLocation -OutputPath "D:\Backups"

Output:

=== Backup-AppxPackage v2.0 ===
Package: 2242AppsTeam.WorkMate v7.5.4.0

[Stage 1/6] Validating inputs...                         ✓
[Stage 2/6] Creating package...                          ✓ (6.4s, 47.95 MB)
[Stage 3/6] Creating certificate...                      ✓
[Stage 4/6] Installing certificate to Trusted Root...    ✓
[Stage 5/6] Signing package...                           ✓

✓ Certificate installed successfully - package is ready to install

To install the package, run:
  Install-AppxBackup -PackagePath 'D:\Backups\WorkMate_7.5.4.0_x64.appx'

Files Created:

D:\Backups\
├── 2242AppsTeam.WorkMate_7.5.4.0_x64__v313ts49xh8we.appx  (47.95 MB, signed)
└── 2242AppsTeam.WorkMate_7.5.4.0_x64__v313ts49xh8we.cer  (certificate)

Step 2: Install on Another Machine

# Single command - auto-detects certificate
Install-AppxBackup -PackagePath "D:\Backups\WorkMate_7.5.4.0_x64.appx"

Output:

=== APPX Package Installation Script ===

[1/3] Package Analysis
  Package: WorkMate_7.5.4.0_x64.appx
  Certificate: Auto-detected (WorkMate_7.5.4.0_x64.cer)

[2/3] Certificate Installation
  Target Store: Cert:\LocalMachine\Root
  Status: Installed successfully
  Thumbprint: 439F89C615A7468BF196D8951BBA4640C10D7D3F

[3/3] Package Installation
  Installing package...
  Status: Installed successfully
  Name: 2242AppsTeam.WorkMate
  Version: 7.5.4.0

=== Installation Complete ===

Available Commands

Public Functions

Function	Description
`Backup-AppxPackage`	Complete backup with cert creation and signing
`Install-AppxBackup`	Installation with auto-cert handling and dependency orchestration
`New-AppxBackupCertificate`	Create self-signed certificates (4096-bit RSA)
`Get-AppxBackupInfo`	Analyze backup packages without installing
`Export-AppxDependencies`	Extract and document package dependencies
`Test-AppxPackageIntegrity`	Validate package structure and signatures
`Test-AppxBackupCompatibility`	Check system compatibility before restore
`Get-AppxToolPath`	Locate Windows SDK tools (MakeAppx, SignTool)

Private Functions (Internal)

Get-AppxConfiguration - Configuration loader from JSON files
Get-AppxDefault - Configuration value accessor with hierarchical fallback
Invoke-ProcessSafely - Robust external process execution with timeout
Get-AppxManifestData - XML manifest parsing with namespace handling
New-AppxPackageInternal - Core packaging logic with multi-tier fallback
Test-AppxToolAvailability - SDK tool validation and caching
Resolve-AppxDependencies - Recursive dependency graph analysis
ConvertTo-SecureFilePath - Path validation and sanitization
Write-AppxLog - Structured logging with level filtering
New-AppxBackupZipArchive - ZIP archive creation for dependency packages
New-AppxBackupManifest - Installation manifest generation
New-AppxDependencyCertificate - Dependency-specific certificate creation
ConvertTo-HtmlEncodedString - HTML entity encoding for safe output
Copy-AppxSourceDirectory - Robust directory copying with multi-tier fallback
Find-AppxSdkTool - Locate SDK tools in Program Files and registry
Get-AppxMakeAppxErrorAnalysis - Parse and interpret MakeAppx error messages
Install-AppxCertificateToStore - Install certificates to certificate stores
Invoke-AppxSignTool - SignTool wrapper with error handling
Remove-AppxItemWithRetry - Retry-based item removal with escalation
Resolve-AppxManifestNode - Resolve XML nodes with namespace fallback
Test-AppxArchitectureCompatibility - Check CPU architecture compatibility
Test-AppxDiskSpace - Validate available disk space
Test-AppxPackagingPrerequisites - Verify SDK tools and system requirements

Usage Examples

For more detailed usage examples, see Examples/UsageExamples.md.

Basic Operations

1. Simple Backup

$app = Get-AppxPackage -Name "Microsoft.WindowsCalculator"
Backup-AppxPackage -PackagePath $app.InstallLocation -OutputPath "C:\Backups"

2. Backup with Custom Certificate

Backup-AppxPackage -PackagePath $app.InstallLocation `
    -OutputPath "C:\Backups" `
    -CertificateSubject "CN=MyCompany Code Signing" `
    -CertificatePassword (ConvertTo-SecureString "MyPassword" -AsPlainText -Force)

3. Skip Certificate (Use Existing)

Backup-AppxPackage -PackagePath $app.InstallLocation `
    -OutputPath "C:\Backups" `
    -NoCertificate

Dependency Operations

4. Backup with Dependencies (ZIP Archive)

# Creates .appxpack file with main package and all dependencies
Backup-AppxPackage -PackagePath $app.InstallLocation `
    -OutputPath "C:\Backups" `
    -IncludeDependencies

5. Dependency Analysis Only (No Backup)

# Creates PackageName_Dependencies.json without creating backup
Backup-AppxPackage -PackagePath $app.InstallLocation `
    -OutputPath "C:\Backups" `
    -DependencyReportOnly

Batch Operations

6. Backup All Apps from a Publisher

Get-AppxPackage -Publisher "*Microsoft*" | 
    ForEach-Object {
        Backup-AppxPackage -PackagePath $_.InstallLocation `
            -OutputPath "D:\Backups\Microsoft" `
            -Verbose
    }

Installation Operations

7. Install Standalone Package

Install-AppxBackup -PackagePath "C:\Backups\MyApp.appx"

8. Install ZIP Archive with Dependencies

Install-AppxBackup -PackagePath "C:\Backups\MyApp.appxpack"

9. Install for Current User Only (No Admin)

Install-AppxBackup -PackagePath "C:\Backups\MyApp.appx" `
    -CertStoreLocation CurrentUser

10. Force Reinstall

Install-AppxBackup -PackagePath "C:\Backups\MyApp.appx" -Force

11. Skip Certificate (Already Trusted)

Install-AppxBackup -PackagePath "C:\Backups\MyApp.appx" -SkipCertificate

12. Allow Unsigned Packages (Developer Mode)

Install-AppxBackup -PackagePath "C:\Backups\MyApp.appx" -AllowUnsigned

Troubleshooting

Common Errors and Solutions

Error: 0x800B0109 (Certificate Not Trusted)

Cause: Certificate not in Trusted Root store
Solution:

# Run as Administrator
Import-Certificate -FilePath "path\to\cert.cer" `
    -CertStoreLocation "Cert:\LocalMachine\Root"

Error: 0x80073CF9 (Already Installed)

Cause: Package already installed
Solution:

Install-AppxBackup -PackagePath "package.appx" -Force

Error: MakeAppx Not Found

Cause: Windows SDK not installed
Solution:

Install Windows SDK from Microsoft

Error: Access Denied (WindowsApps)

Cause: Insufficient permissions
Solution:

Module automatically uses multi-tier copy fallback
Robocopy → Copy-Item → .NET APIs
No manual intervention needed

Limitations

Restoration Behavior

Some applications cannot be successfully restored after being repackaged. If a repackaged application fails to install, the application cannot be used from the backup. Reinstall from the Microsoft Store.

Module Architecture

AppxBackup.Module/
├── AppxBackup.psd1           # Module manifest
├── AppxBackup.psm1           # Module loader
├── Test-AppxBackupModule.ps1 # Module test suite
├── Import-AppxBackup.ps1     # Quick import helper
│
├── Config/                   # Externalized configuration
│   ├── ModuleDefaults.json           # Core module constants
│   ├── ToolConfiguration.json        # Tool-specific settings
│   ├── WindowsReservedNames.json     # Reserved filenames
│   ├── PackageConfiguration.json     # Package-related constants
│   └── ZipPackagingConfiguration.json # ZIP archive settings
│
├── Public/                   # Exported functions
│   ├── Backup-AppxPackage.ps1          # Main backup function
│   ├── Install-AppxBackup.ps1          # Package installer (Restore-AppxPackage alias)
│   ├── New-AppxBackupCertificate.ps1   # Certificate creation
│   ├── Get-AppxBackupInfo.ps1          # Package analysis
│   ├── Export-AppxDependencies.ps1     # Dependency export
│   ├── Test-AppxPackageIntegrity.ps1   # Integrity validation
│   ├── Test-AppxBackupCompatibility.ps1 # Compatibility check
│   └── Get-AppxToolPath.ps1            # Tool locator
│
├── Private/                  # Internal functions
│   ├── Get-AppxConfiguration.ps1       # Configuration loader
│   ├── Get-AppxDefault.ps1             # Configuration value accessor
│   ├── Invoke-ProcessSafely.ps1        # Process execution
│   ├── Get-AppxManifestData.ps1        # Manifest parsing
│   ├── New-AppxPackageInternal.ps1     # Core packaging logic
│   ├── Test-AppxToolAvailability.ps1   # Tool validation
│   ├── Resolve-AppxDependencies.ps1    # Dependency resolution
│   ├── ConvertTo-SecureFilePath.ps1    # Path sanitization
│   ├── Write-AppxLog.ps1               # Logging system
│   ├── New-AppxBackupZipArchive.ps1    # ZIP archive creation
│   ├── New-AppxBackupManifest.ps1      # Installation manifest generation
│   ├── New-AppxDependencyCertificate.ps1 # Dependency certificate creation
│   ├── ConvertTo-HtmlEncodedString.ps1 # HTML encoding
│   ├── Copy-AppxSourceDirectory.ps1    # Directory copying
│   ├── Find-AppxSdkTool.ps1            # SDK tool locator
│   ├── Get-AppxMakeAppxErrorAnalysis.ps1 # MakeAppx error parser
│   ├── Install-AppxCertificateToStore.ps1 # Certificate installation
│   ├── Invoke-AppxSignTool.ps1         # SignTool wrapper
│   ├── Remove-AppxItemWithRetry.ps1    # Retry-based removal
│   ├── Resolve-AppxManifestNode.ps1    # XML node resolution
│   ├── Test-AppxArchitectureCompatibility.ps1 # Architecture check
│   ├── Test-AppxDiskSpace.ps1          # Disk space validation
│   └── Test-AppxPackagingPrerequisites.ps1 # Prerequisites check
│
└── Examples/                 # Usage examples
    └── UsageExamples.md

Testing Infrastructure

Test-AppxBackupModule.ps1

A comprehensive test harness that validates all 8 exported public functions with multiple parameter combinations.

Automatic app discovery via Get-AppxPackage pattern matching eliminates manual configuration. Full console transcript and structured results file saved to timestamped test run directories.

Usage:

# Test with custom app and output folder
.\Test-AppxBackupModule.ps1 -TestFolder "C:\Temp\AppxTest\" -AppName "Netflix"

# Include destructive installation test (optional)
.\Test-AppxBackupModule.ps1 -TestFolder "C:\Temp\" -AppName "Spotify" -TestInstall

Results include pass/fail/skip/error counts, detailed timing, and structured output suitable for CI/CD integration.

Configuration System

All hardcoded values are externalized to JSON configuration files in the Config/ directory:

ModuleDefaults.json - Path limits, timeouts, buffer sizes, disk space thresholds, etc.
ToolConfiguration.json - Tool-specific timeouts, async wait times, exit code interpretation
WindowsReservedNames.json - Windows reserved filenames for validation
PackageConfiguration.json - Package extensions, signature files, compression levels, namespaces
ZipPackagingConfiguration.json - ZIP archive structure, compression settings, manifest defaults, system requirements

Support

Getting Help

Documentation: Enter help Command (e. g. help Backup-AppxPackage)
Examples: See /Examples/UsageExamples.md
Issues: Check logs in $env:TEMP\AppxBackup_*.log

Reporting Issues

When reporting issues, include:

PowerShell version ($PSVersionTable)
Windows version (Get-ComputerInfo | Select OSName, OSVersion)
Error message and stack trace
Log file from $env:TEMP\AppxBackup_*.log

Changelog

Version 2.0.2 (February 13, 2026)

Code Quality & Maintainability

Extracted 11 new private helper functions to improve code organization and testability.
Refactored core functions (Backup-AppxPackage, New-AppxPackageInternal) by removing ~600 lines of duplicate/embedded logic.

Future Changes (Planned)

Nothing explicitly planned for future versions.

Citations

Original Repository

mjmeans/Appx-Backup: PowerShell script to backup an installed Windows Store App to an installable Appx file. (2016). GitHub.

Name		Name	Last commit message	Last commit date
Latest commit History 41 Commits
Assets		Assets
Config		Config
Examples		Examples
Private		Private
Public		Public
.gitattributes		.gitattributes
AppxBackup.psd1		AppxBackup.psd1
AppxBackup.psm1		AppxBackup.psm1
Import-AppxBackup.ps1		Import-AppxBackup.ps1
LICENSE		LICENSE
README.md		README.md
Test-AppxBackupModule.ps1		Test-AppxBackupModule.ps1

License

DeltaGa/AppxBackup.Module

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