Update using-custom-rewrite-providers-with-url-rewrite-module.md (#1069)

* Update using-custom-rewrite-providers-with-url-rewrite-module.md

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Third part saved download link: https://web.archive.org/web/20200801000000id_/download.microsoft.com/download/3/9/E/39E30671-7AD2-4902-B56B-C300D862595E/RewriteExtensibility.msi
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* Update iis/extensions/url-rewrite-module/using-custom-rewrite-providers-with-url-rewrite-module.md

Linked to URL Rewrite 2.1 module as has been suggested previously by IIS team's Sam Wu.

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Co-authored-by: Wade Pickett <[email protected]>

iis/extensions/url-rewrite-module/using-custom-rewrite-providers-with-url-rewrite-module.md

@@ -15,7 +15,7 @@ This walkthrough will guide you through how to use custom rewrite providers with
 
 ## Install URL Rewrite Extensibility Samples
 
-In order to complete this walkthrough, download and install URL Rewrite Extensibility Samples (`https://www.microsoft.com/download/details.aspx?id=43353`). The Extensibility Samples installation package includes .NET assemblies and the source code with full implementation of rewrite providers for the three most common use cases:
+In order to complete this walkthrough, download and install [IIS URL Rewrite 2.1](https://iis-umbraco.azurewebsites.net/downloads/microsoft/url-rewrite). The URL Rewrite Extensibility Samples for 2.0 are no longer available.
 
 - Storing of the rewrite or redirect mappings in a SQL database;
 - Storing of the rewrite or redirect mappings in a text file;