Implement easyEXCH ProxyAddress Manager for MS365 ADSync environments

[Copilot]

PowerShell tool with WPF GUI for managing Active Directory ProxyMailAddresses in MS365 ADSync environments without local Exchange Server.

Core Implementation

Main Application (easyEXCH-ProxyMailAddresses.ps1, 664 lines)

• WPF GUI with XAML-defined interface
• User search via DisplayName, SamAccountName, or Mail
• ProxyAddress operations: view, add, remove, set primary
• Automatic primary address demotion when setting new primary

Key Technical Decisions

• Email validation: .NET System.Net.Mail.MailAddress class instead of regex for RFC compliance
• AD queries: -ResultSetSize parameter vs Select-Object -First for server-side limiting
• WPF threading: Dispatcher.Invoke() vs DoEvents() to prevent reentrancy
• XAML events: Add_EventName() methods in PowerShell (inline handlers unsupported)

# ProxyAddress format: uppercase TYPE = primary, lowercase = secondary
SMTP:user@domain.com    # Primary
smtp:alias@domain.com   # Secondary

# Setting primary demotes existing primary automatically
Set-ADUser -Identity $user -Replace @{ProxyAddresses=$newAddresses}

Documentation

• README.md: Feature overview, installation, usage patterns
• QUICKSTART.md: 3-step onboarding with common tasks
• INSTALLATION.md: RSAT setup, prerequisites, troubleshooting
• EXAMPLES.md: MS365 migration, department changes, multi-alias scenarios
• SECURITY.md: Least privilege model, audit logging, compliance considerations
• CHANGELOG.md: Version history and roadmap

Security

• Input validation using .NET MailAddress
• Confirmation dialogs for destructive operations (with extra warning for primary SMTP removal)
• AD permissions: read User objects, write ProxyAddresses only (no Domain Admin required)
• Query result limiting (50 users) for resource protection

Original prompt

easyEXCH ProxyAddress Manager ist ein PowerShell-basiertes Tool mit moderner WPF-GUI zur Verwaltung von ProxyMailAddresses in Active Directory. Es wurde speziell für Umgebungen entwickelt, in denen kein lokaler Exchange Server mehr vorhanden ist, aber MS365 ADSync verwendet wird.

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