diff --git a/tests/unit/framework/web/ResponseTest.php b/tests/unit/framework/web/ResponseTest.php
new file mode 100644
index 0000000..b3d9080
--- /dev/null
+++ b/tests/unit/framework/web/ResponseTest.php
@@ -0,0 +1,86 @@
+<?php
+
+namespace yii\web;
+
+use yiiunit\framework\web\ResponseTest;
+
+/**
+ * Mock PHP header function to check for sent headers
+ * @param string $string
+ * @param bool $replace
+ * @param int $httpResponseCode
+ */
+function header($string, $replace = true, $httpResponseCode = null) {
+	ResponseTest::$headers[] = $string;
+	// TODO implement replace
+
+	if ($httpResponseCode !== null) {
+		ResponseTest::$httpResponseCode = $httpResponseCode;
+	}
+}
+
+namespace yiiunit\framework\web;
+
+use yii\helpers\StringHelper;
+use yii\web\Response;
+
+class ResponseTest extends \yiiunit\TestCase
+{
+	public static $headers = array();
+	public static $httpResponseCode = 200;
+
+	protected function setUp()
+	{
+		parent::setUp();
+		$this->reset();
+	}
+
+	protected function reset()
+	{
+		static::$headers = array();
+		static::$httpResponseCode = 200;
+	}
+
+	public function ranges()
+	{
+		// TODO test more cases for range requests and check for rfc compatibility
+		// http://www.w3.org/Protocols/rfc2616/rfc2616.txt
+		return array(
+			array('0-5', '0-5', 6, '12ёж'),
+			array('2-', '2-66', 65, 'ёжик3456798áèabcdefghijklmnopqrstuvwxyz!"§$%&/(ёжик)=?'),
+			array('-12', '55-66', 12, '(ёжик)=?'),
+		);
+	}
+
+	/**
+	 * @dataProvider ranges
+	 */
+	public function testSendFileRanges($rangeHeader, $expectedHeader, $length, $expectedFile)
+	{
+		$content = $this->generateTestFileContent();
+
+		$_SERVER['HTTP_RANGE'] = 'bytes=' . $rangeHeader;
+		$sent = $this->runSendFile('testFile.txt', $content, null);
+		$this->assertEquals($expectedFile, $sent);
+		$this->assertTrue(in_array('HTTP/1.1 206 Partial Content', static::$headers));
+		$this->assertTrue(in_array('Accept-Ranges: bytes', static::$headers));
+		$this->assertArrayHasKey('Content-Range: bytes ' . $expectedHeader . '/' . StringHelper::strlen($content), array_flip(static::$headers));
+		$this->assertTrue(in_array('Content-Type: text/plain', static::$headers));
+		$this->assertTrue(in_array('Content-Length: ' . $length, static::$headers));
+	}
+
+	protected function generateTestFileContent()
+	{
+		return '12ёжик3456798áèabcdefghijklmnopqrstuvwxyz!"§$%&/(ёжик)=?';
+	}
+
+	protected function runSendFile($fileName, $content, $mimeType)
+	{
+		ob_start();
+		ob_implicit_flush(false);
+		$response = new Response();
+		$response->sendFile($fileName, $content, $mimeType, false);
+		$file = ob_get_clean();
+		return $file;
+	}
+}
\ No newline at end of file
diff --git a/yii/base/ErrorHandler.php b/yii/base/ErrorHandler.php
index 44c2ca0..8340723 100644
--- a/yii/base/ErrorHandler.php
+++ b/yii/base/ErrorHandler.php
@@ -75,8 +75,11 @@ class ErrorHandler extends Component
 			\Yii::$app->runAction($this->errorAction);
 		} elseif (\Yii::$app instanceof \yii\web\Application) {
 			if (!headers_sent()) {
-				$errorCode = $exception instanceof HttpException ? $exception->statusCode : 500;
-				header("HTTP/1.0 $errorCode " . get_class($exception));
+				if ($exception instanceof HttpException) {
+					header('HTTP/1.0 ' . $exception->statusCode . ' ' . $exception->getName());
+				} else {
+					header('HTTP/1.0 500 ' . get_class($exception));
+				}
 			}
 			if (isset($_SERVER['HTTP_X_REQUESTED_WITH']) && $_SERVER['HTTP_X_REQUESTED_WITH'] === 'XMLHttpRequest') {
 				\Yii::$app->renderException($exception);
diff --git a/yii/web/Response.php b/yii/web/Response.php
index 54b7f6e..954c999 100644
--- a/yii/web/Response.php
+++ b/yii/web/Response.php
@@ -8,8 +8,10 @@
 namespace yii\web;
 
 use Yii;
+use yii\base\HttpException;
 use yii\helpers\FileHelper;
 use yii\helpers\Html;
+use yii\helpers\StringHelper;
 
 /**
  * @author Qiang Xue <qiang.xue@gmail.com>
@@ -31,27 +33,76 @@ class Response extends \yii\base\Response
 	 * @param string $content content to be set.
 	 * @param string $mimeType mime type of the content. If null, it will be guessed automatically based on the given file name.
 	 * @param boolean $terminate whether to terminate the current application after calling this method
-	 * @todo
+	 * @throws \yii\base\HttpException when range request is not satisfiable.
 	 */
 	public function sendFile($fileName, $content, $mimeType = null, $terminate = true)
 	{
-		if ($mimeType === null && ($mimeType = FileHelper::getMimeType($fileName)) === null) {
+		if ($mimeType === null && (($mimeType = FileHelper::getMimeTypeByExtension($fileName)) === null)) {
 			$mimeType = 'application/octet-stream';
 		}
+
+		$fileSize = StringHelper::strlen($content);
+		$contentStart = 0;
+		$contentEnd = $fileSize - 1;
+
+		// tell the client that we accept range requests
+		header('Accept-Ranges: bytes');
+
+		if (isset($_SERVER['HTTP_RANGE'])) {
+			// client sent us a multibyte range, can not hold this one for now
+			if (strpos(',', $_SERVER['HTTP_RANGE']) !== false) {
+				header("Content-Range: bytes $contentStart-$contentEnd/$fileSize");
+				throw new HttpException(416, 'Requested Range Not Satisfiable');
+			}
+
+			$range = str_replace('bytes=', '', $_SERVER['HTTP_RANGE']);
+
+			// range requests starts from "-", so it means that data must be dumped the end point.
+			if ($range[0] === '-') {
+				$contentStart = $fileSize - substr($range, 1);
+			} else {
+				$range = explode('-', $range);
+				$contentStart = $range[0];
+				$contentEnd = (isset($range[1]) && is_numeric($range[1])) ? $range[1] : $fileSize - 1;
+			}
+
+			/* Check the range and make sure it's treated according to the specs.
+			 * http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html
+			 */
+			// End bytes can not be larger than $end.
+			$contentEnd = ($contentEnd > $fileSize) ? $fileSize : $contentEnd;
+
+			// Validate the requested range and return an error if it's not correct.
+			$wrongContentStart = ($contentStart > $contentEnd || $contentStart > $fileSize - 1 || $contentStart < 0);
+
+			if ($wrongContentStart) {   
+				header("Content-Range: bytes $contentStart-$contentEnd/$fileSize");
+				throw new HttpException(416, 'Requested Range Not Satisfiable');
+			}
+
+			header('HTTP/1.1 206 Partial Content');
+			header("Content-Range: bytes $contentStart-$contentEnd/$fileSize");
+		} else {
+			header('HTTP/1.1 200 OK');
+		}
+
+		$length = $contentEnd - $contentStart + 1; // Calculate new content length
+
 		header('Pragma: public');
 		header('Expires: 0');
 		header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
-		header("Content-type: $mimeType");
-		if (ob_get_length() === false) {
-			header('Content-Length: ' . (function_exists('mb_strlen') ? mb_strlen($content, '8bit') : strlen($content)));
-		}
-		header("Content-Disposition: attachment; filename=\"$fileName\"");
+		header('Content-Type: ' . $mimeType);
+		header('Content-Length: ' . $length);
+		header('Content-Disposition: attachment; filename="' . $fileName . '"');
 		header('Content-Transfer-Encoding: binary');
+		$content = StringHelper::substr($content, $contentStart, $length);
 
 		if ($terminate) {
 			// clean up the application first because the file downloading could take long time
 			// which may cause timeout of some resources (such as DB connection)
-			Yii::app()->end(0, false);
+			ob_start();
+			Yii::$app->end(0, false);
+			ob_end_clean();
 			echo $content;
 			exit(0);
 		} else {