There is no reason you can’t run WordPress in IIS and still have good looking URLs. The rule below is simply a conversion from the de facto Apache .htaccess rule which allows SEO-friendly URLs within WordPress.

Add the following rule to the <rules> section of web.confg:

<system.webServer>
	<rewrite>
		<rules>
			<rule name="WordPress SEO URLs" stopProcessing="true">
				<match url=".*" />
				<conditions>
					<add input="{REQUEST_FILENAME}" matchType="IsFile" negate="true" />
					<add input="{REQUEST_FILENAME}" matchType="IsDirectory" negate="true" />
				</conditions>
				<action type="Rewrite" url="index.php" />
			</rule>
		</rules>
	</rewrite>
</system.webServer>

This rule allows you to now use any type of permalink in the WordPress’ Settings > Permalink pane; without it, you’d be limited to just the Plain type of permalink which looks like https://www.example.com/?p=123 , rather than https://www.example.com/your-fancy-post-name/.