Binding Redirect Fixer

A Visual Studio 2026 extension that automatically detects and repairs stale, missing, or orphaned assembly binding redirects in .NET Framework and .NET (Core) projects.

The Problem

After NuGet updates or partial deployments, binding redirects in web.config / app.config often reference wrong assembly versions, causing runtime errors like:

Could not load file or assembly 'Newtonsoft.Json, Version=12.0.0.0, ...' manifest definition does not match the assembly reference.

Tracking down which redirects are wrong and what versions they should point to is tedious and error-prone. This extension automates the entire process.

Features

• Automatic Detection -- scans all projects in your solution for stale, missing, orphaned, conflicting, or critically mismatched binding redirects
• Multi-Source Version Resolution -- cross-references four independent sources to pinpoint exactly where versions diverge:
  1. NuGet resolved DLL (authoritative)
  2. Package reference version (cross-check)
  3. Physical DLL in bin/ -- walks bin/runtimes/<rid>/lib/<tfm>/ too, top-level DLL wins on duplicate names
  4. Config redirect (what the runtime uses)
• Smart Fix Actions -- updates stale redirects, adds missing ones, removes duplicates, or rebuilds projects with conflicting bin/ output. High-risk removals (orphaned .NET Framework) route through a guided flow with safety checks instead of a single click.
• Fix Shown Items / Fix All -- batch-fix the currently visible issues. The guided orphan-.NET-Framework flow is excluded from bulk operations -- each must be reviewed individually.
• Critical Mismatch Detection -- flags redirects pointing forward to a version that exists nowhere on disk; runtime FileLoadException at startup is guaranteed. Auto-updates to the highest version available on disk.
• Guided Orphan Removal (.NET Framework) -- runs three automated safety checks (solution-wide source-usage grep, GAC folder probe, transitive bin/ reference scan via MetadataLoadContext) plus surfaces the project's <PostBuildEvent> for manual review. Remove Redirect only enables when every auto check passes AND the manual confirmation is ticked. If a check fails, the panel routes you to Open Config File for Manual Editing instead.
• Build-Required Banner -- when the scan finds no on-disk DLLs for any redirect (project not built, NuGet not restored), a banner explains that detection is degraded and prompts to build + restore first.
• Deprecated Package Detection -- flags packages like Microsoft.Azure.Services.AppAuthentication with migration guidance and offers removal with a warning
• DLL Project Redirect Cleanup -- detects class library projects where binding redirects have no effect (CLR only reads host app config) and offers bulk removal of the entire section or file
• Framework Detection -- reads target framework from .csproj to provide framework-specific guidance, including detection of legacy ASP.NET Web Application Projects (WAPs)
• Supports Both Project Types -- works with PackageReference and packages.config projects
• Parallel Scanning -- analyses up to 5 projects concurrently with real-time progress ("Analysing 3 of 12: ProjectName...")
• Resizable & Sortable Columns -- drag column borders to resize, click headers to sort ascending/descending
• Educational UI -- a built-in Background tab explains what binding redirects are, why they break, how this tool resolves them, and how the orphan-safety checks work
• Theme-Aware -- fully adapts to Light, Dark, Blue, and High Contrast themes
• Non-Destructive -- creates timestamped backups before modifying any config file

Installation

From Visual Studio Marketplace

1. Open Visual Studio 2026
2. Go to Extensions > Manage Extensions
3. Search for "Binding Redirect Fixer"
4. Click Download and restart Visual Studio

From VSIX File

1. Download the .vsix file from Releases
2. Double-click the file to install, or use Extensions > Manage Extensions > Install from File

Usage

1. Open a solution containing .NET Framework projects with web.config or app.config
2. Go to Tools > Binding Redirect Fixer
3. The tool window opens and automatically scans your solution
4. Review the detected issues in the multi-source grid
5. Click Fix All to resolve all issues, or fix them individually

How It Works

The extension reads assembly versions from multiple sources and compares them:

Source	What It Represents	Trust Level
NuGet Resolved DLL	The actual DLL from the NuGet cache	Authoritative
Package Reference	What was requested in .csproj / packages.config	Cross-check
bin/ DLL	What is physically on disk	Can be stale
Config Redirect	What the runtime currently uses	Often wrong

Issue Types

Status	Meaning	Auto-Fix
STALE	Config redirect points to an old assembly version	Updates newVersion to the resolved version
MISSING	Multiple packages need different versions but no redirect exists	Adds a new <dependentAssembly> element
CONFLICT	Config is correct but the bin/ DLL is outdated	Triggers a clean rebuild
DUPLICATE	Multiple redirects exist for the same assembly	Removes the duplicate entry
MISMATCH	Redirect targets a version not available on disk (bin/ DLL is older than NuGet resolved)	Removes the redirect so the runtime loads the bin/ DLL directly
CRITICAL MISMATCH	Redirect points FORWARD to a version greater than the highest DLL on disk -- runtime FileLoadException at startup is guaranteed	Updates newVersion to the highest version available on disk
TOKEN LOST	DLL exists but is unsigned while config expects a public key token	Preserves token, updates version if needed
DEPRECATED	Package is deprecated and should be replaced with a modern equivalent (e.g., AppAuthentication -> Azure.Identity)	Removes redirect (with warning to check NuGet refs)
ORPHANED .NET (Core)	No DLL found in a .NET (Core) project -- redirect is orphaned	Removes the redirect (safe)
ORPHANED .NET Framework	No DLL found in a .NET Framework project -- redirect is likely orphaned, but GAC / post-build / transitive bin refs could still depend on it	Opens an inline guided-removal panel: runs three automated safety checks (source-usage grep, GAC probe, transitive bin/ references) and surfaces the .csproj post-build script for manual review. Remove Redirect is only enabled when every auto check passes AND the manual confirmation is ticked.
UNUSED IN LIBRARY	Binding redirect in a class library (DLL) project -- CLR never reads DLL config files	Removes all redirects (section or file deletion)

Package Version vs Assembly Version

Binding redirects operate on assembly versions, not NuGet package versions. These are often different:

Package version:  Newtonsoft.Json 13.0.3
Assembly version: Newtonsoft.Json 13.0.0.0

This extension resolves the actual assembly version by reading the DLL from the NuGet cache using MetadataLoadContext (no file locking).

Requirements

• Visual Studio 2026 (18.0+) or Visual Studio 2022 17.14+
• .NET Framework projects with web.config or app.config
• NuGet packages restored (the extension will prompt you if project.assets.json is missing)

Tech Stack

• VisualStudio.Extensibility (out-of-proc model)
• Remote UI with XAML (WPF-compatible, theme-aware)
• NuGet.ProjectModel for project.assets.json parsing
• System.Reflection.MetadataLoadContext for non-locking DLL inspection
• System.Xml.Linq for config file manipulation

Contributing

Contributions are welcome! Please open an issue first to discuss what you would like to change.

1. Fork the repository
2. Create your feature branch (git checkout -b feature/my-feature)
3. Commit your changes (git commit -m 'Add my feature')
4. Push to the branch (git push origin feature/my-feature)
5. Open a Pull Request

License

MIT

Author

Ardimedia