AppIconPatcher

AppIconPatcher is a Windows GUI application (EXE) for patching an application's icon resources using a selected .ico file.

Features

• Desktop GUI with an installed-app dropdown (auto-discovered from registry/start menu) and manual file pickers
  • Installed app selector (auto-fills executable path)
  • Target executable (.exe)
  • Source icon (.ico)
• Optional backup creation (<exe>.bak) before patching
• Configurable RT_GROUP_ICON ID and language ID
• Writes both:
  • RT_ICON resources for each image in the ICO
  • RT_GROUP_ICON resource that references those icon images

Build the EXE

On Windows with .NET 8 SDK installed:

dotnet publish .\src\AppIconPatcher.Gui\AppIconPatcher.Gui.csproj -c Release -r win-x64 --self-contained true /p:PublishSingleFile=true

Published output:

• src\AppIconPatcher.Gui\bin\Release\net8.0-windows\win-x64\publish\AppIconPatcher.exe

Run from source

dotnet run --project .\src\AppIconPatcher.Gui\AppIconPatcher.Gui.csproj

Notes

• Patch only binaries you own and are allowed to modify.
• Modifying resources usually invalidates code signatures.
• You may need to refresh icon cache or restart Explorer to see icon updates immediately.