diff --git a/tests/phpunit/tests/admin/includes/misc/iis7DeleteRewriteRule.php b/tests/phpunit/tests/admin/includes/misc/iis7DeleteRewriteRule.php
new file mode 100644
index 0000000000000..3954001cef4f5
--- /dev/null
+++ b/tests/phpunit/tests/admin/includes/misc/iis7DeleteRewriteRule.php
@@ -0,0 +1,130 @@
+<?php
+
+/**
+ * Tests for the iis7_delete_rewrite_rule() function.
+ *
+ * @group admin
+ *
+ * @covers ::iis7_delete_rewrite_rule
+ */
+class Tests_iis7_delete_rewrite_rule extends WP_UnitTestCase {
+
+	/**
+	 * Path to the temporary file.
+	 *
+	 * @var string
+	 */
+	private $temp_file;
+
+	/**
+	 * Set up the test environment.
+	 */
+	public function set_up() {
+		parent::set_up();
+
+		require_once ABSPATH . 'wp-admin/includes/misc.php';
+
+		$this->temp_file = wp_tempnam( 'web.config' );
+	}
+
+	/**
+	 * Clean up the test environment.
+	 */
+	public function tear_down() {
+		if ( file_exists( $this->temp_file ) ) {
+			unlink( $this->temp_file );
+		}
+
+		parent::tear_down();
+	}
+
+	/**
+	 * Tests that iis7_delete_rewrite_rule() correctly deletes WordPress rules.
+	 *
+	 * @ticket 65170
+	 *
+	 * @dataProvider data_iis7_delete_rewrite_rule
+	 *
+	 * @param string $initial_content  The initial XML content of the file.
+	 * @param string $expected_content The expected XML content after deletion.
+	 */
+	public function test_iis7_delete_rewrite_rule( $initial_content, $expected_content ) {
+		file_put_contents( $this->temp_file, $initial_content );
+
+		$result = iis7_delete_rewrite_rule( $this->temp_file );
+
+		$this->assertTrue( $result, 'iis7_delete_rewrite_rule() should return true on success.' );
+
+		if ( '' === $expected_content ) {
+			$this->assertStringEqualsFile( $this->temp_file, '', 'The file should be empty.' );
+		} else {
+			$this->assertXmlStringEqualsXmlFile( $this->temp_file, $expected_content, 'The XML content should match the expected output.' );
+		}
+	}
+
+	/**
+	 * Data provider for test_iis7_delete_rewrite_rule.
+	 *
+	 * @return array<string, array{
+	 *     initial_content:  string,
+	 *     expected_content: string,
+	 * }>
+	 */
+	public function data_iis7_delete_rewrite_rule(): array {
+		return array(
+			'Rule with name "wordpress" exists'            => array(
+				'initial_content'  => '<configuration><system.webServer><rewrite><rules><rule name="wordpress" /></rules></rewrite></system.webServer></configuration>',
+				'expected_content' => '<configuration><system.webServer><rewrite><rules/></rewrite></system.webServer></configuration>',
+			),
+			'Rule with name starting with "wordpress" exists' => array(
+				'initial_content'  => '<configuration><system.webServer><rewrite><rules><rule name="wordpress-rules" /></rules></rewrite></system.webServer></configuration>',
+				'expected_content' => '<configuration><system.webServer><rewrite><rules/></rewrite></system.webServer></configuration>',
+			),
+			'Rule with name "WordPress" exists'            => array(
+				'initial_content'  => '<configuration><system.webServer><rewrite><rules><rule name="WordPress" /></rules></rewrite></system.webServer></configuration>',
+				'expected_content' => '<configuration><system.webServer><rewrite><rules/></rewrite></system.webServer></configuration>',
+			),
+			'Multiple rules, only WordPress rule is deleted' => array(
+				'initial_content'  => '<configuration><system.webServer><rewrite><rules><rule name="other-rule" /><rule name="wordpress" /></rules></rewrite></system.webServer></configuration>',
+				'expected_content' => '<configuration><system.webServer><rewrite><rules><rule name="other-rule" /></rules></rewrite></system.webServer></configuration>',
+			),
+			'WordPress rule is first among multiple rules' => array(
+				'initial_content'  => '<configuration><system.webServer><rewrite><rules><rule name="wordpress" /><rule name="other-rule" /></rules></rewrite></system.webServer></configuration>',
+				'expected_content' => '<configuration><system.webServer><rewrite><rules><rule name="other-rule" /></rules></rewrite></system.webServer></configuration>',
+			),
+			'No WordPress rule exists'                     => array(
+				'initial_content'  => '<configuration><system.webServer><rewrite><rules><rule name="other-rule" /></rules></rewrite></system.webServer></configuration>',
+				'expected_content' => '<configuration><system.webServer><rewrite><rules><rule name="other-rule" /></rules></rewrite></system.webServer></configuration>',
+			),
+			'Empty rules tag'                              => array(
+				'initial_content'  => '<configuration><system.webServer><rewrite><rules/></rewrite></system.webServer></configuration>',
+				'expected_content' => '<configuration><system.webServer><rewrite><rules/></rewrite></system.webServer></configuration>',
+			),
+		);
+	}
+
+	/**
+	 * Tests that iis7_delete_rewrite_rule() returns true if the file does not exist.
+	 *
+	 * @ticket 65170
+	 */
+	public function test_iis7_delete_rewrite_rule_non_existent_file() {
+		$non_existent_file = dirname( $this->temp_file ) . '/non-existent-web.config';
+		if ( file_exists( $non_existent_file ) ) {
+			unlink( $non_existent_file );
+		}
+
+		$this->assertTrue( iis7_delete_rewrite_rule( $non_existent_file ), 'Should return true if the file does not exist.' );
+	}
+
+	/**
+	 * Tests that iis7_delete_rewrite_rule() returns false for invalid XML.
+	 *
+	 * @ticket 65170
+	 */
+	public function test_iis7_delete_rewrite_rule_invalid_xml() {
+		file_put_contents( $this->temp_file, 'Not XML' );
+		// phpcs:ignore WordPress.PHP.NoSilencedErrors.Discouraged
+		$this->assertFalse( @iis7_delete_rewrite_rule( $this->temp_file ), 'Should return false for invalid XML.' );
+	}
+}