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# Challenge 01 — Assess the Legacy .NET Application

## Introduction

Before touching any code, experienced modernization teams always start with a thorough **assessment**. An assessment surfaces the migration complexity, identifies deprecated APIs, incompatible dependencies, and cloud-readiness gaps — before you write a single line of new code.

The GitHub Copilot Modernization tool provides an assessment capability (accessible from both the CLI and the VS Code panel) that analyses your codebase and produces a structured report. Understanding this report is the foundation for every subsequent challenge.

In this challenge you will run an assessment on the .NET ContosoUniversity application and learn to read the output critically.

## Description

Run the GitHub Copilot Modernization assessment on the .NET sample application located under `Student/Resources/dotnet/dotnet-migration-copilot-samples/ContosoUniversity`. Use the tool's documentation or the VS Code extension to discover how to trigger an assessment.

Review the generated assessment report and discuss as a team:

- How many total issues were found, and how are they distributed across the mandatory, potential, and optional categories?
- Which dependencies or APIs are flagged as unsupported or deprecated?
- What cloud-readiness issues are identified (e.g., local file system usage, MSMQ)?
- Based on the upgrade issues found, what should the migration target be (runtime version, framework version)?
- Are there any breaking changes the tool cannot automatically fix?

## Success Criteria

To complete this challenge successfully, demonstrate:

1. An assessment report exists for the ContosoUniversity (.NET) application
2. Your team can articulate the **top mandatory blockers** for the application (dependencies, APIs, or patterns that require manual attention)
3. Your team has identified which modernization steps the tool can automate vs. which require manual intervention
4. **Explain to your coach** — what is the difference between a **mandatory blocker** and a **potential issue** in the assessment report? Which category would block you from proceeding with the migration?

## Learning Resources

- [Modernization assessment overview](https://learn.microsoft.com/en-us/azure/developer/github-copilot-app-modernization/modernization-agent/overview)
- [.NET upgrade compatibility — dotnet-appcat](https://learn.microsoft.com/dotnet/core/porting/upgrade-assistant-overview)

## Tips

- The GitHub Copilot Modernization tool can be used from both the terminal and the VS Code extension panel. Explore both interfaces — they produce the same report but may suit different workflows.