Update index.md

Author: ccbogel

docs/doc/en/index.md

@@ -28,7 +28,7 @@ Software releases are available from [GitHub](https://github.com/ccbogel/QualCod
 
 [:fontawesome-brands-windows: QualCoder_4.0 Win_INSTALLER.exe](/latest-windows){ .md-button .md-button--primary }
 
-<!-- [:fontawesome-brands-windows: QualCoder_4.0 Windows 11 Portable (Entire software in one file, slower to start)](/latest-windows-portable){ .md-button .md-button--primary } -->
+[:fontawesome-brands-windows: Qualcoder_4.0_PORTABLE.exe (Entire software in one file, slower to start)](https://github.com/ccbogel/QualCoder/releases/download/4.0/Qualcoder-4.0_Win_PORTABLE.exe)
 
 [:material-apple: QualCoder_4.0 macOS arm64](/latest-mac){ .md-button .md-button--primary }
 
@@ -58,4 +58,4 @@ Replace the version number (4.0) as needed for the version you are using.
 
 ## License
 
-QualCoder is licensed under the LGPL v3 licence.
+QualCoder is licensed under the LGPL v3 licence.