5 files changed, 6 insertions, 6 deletions
diff --git a/phpBB/feed.php b/phpBB/feed.php
index 8971bae768..68cb7b9844 100644
--- a/phpBB/feed.php
+++ b/phpBB/feed.php
@@ -164,7 +164,7 @@ if (defined('DEBUG') && request_var('explain', 0) && $auth->acl_get('a_'))
 {
 	header('Content-type: text/html; charset=UTF-8');
 	header('Cache-Control: private, no-cache="set-cookie"');
-	header('Expires: 0');
+	header('Expires: ' . gmdate('D, d M Y H:i:s \G\M\T', time()));
 	header('Pragma: no-cache');
 
 	$mtime = explode(' ', microtime());
diff --git a/phpBB/includes/functions.php b/phpBB/includes/functions.php
index 7dfaea6f48..3387943701 100644
--- a/phpBB/includes/functions.php
+++ b/phpBB/includes/functions.php
@@ -5062,7 +5062,7 @@ function page_header($page_title = '', $display_online_list = false, $item_id =
 		// application/xhtml+xml not used because of IE
 		'Content-type' => 'text/html; charset=UTF-8',
 		'Cache-Control' => 'private, no-cache="set-cookie"',
-		'Expires' => '0',
+		'Expires' => gmdate('D, d M Y H:i:s \G\M\T', time()),
 		'Pragma' => 'no-cache',
 	);
 	if (!empty($user->data['is_bot']))
diff --git a/phpBB/includes/functions_acp.php b/phpBB/includes/functions_acp.php
index d9dc11239c..63d13fb37c 100644
--- a/phpBB/includes/functions_acp.php
+++ b/phpBB/includes/functions_acp.php
@@ -112,7 +112,7 @@ function adm_page_header($page_title)
 		// application/xhtml+xml not used because of IE
 		'Content-type' => 'text/html; charset=UTF-8',
 		'Cache-Control' => 'private, no-cache="set-cookie"',
-		'Expires' => '0',
+		'Expires' => gmdate('D, d M Y H:i:s \G\M\T', time()),
 		'Pragma' => 'no-cache',
 	);
 
diff --git a/phpBB/includes/functions_download.php b/phpBB/includes/functions_download.php
index 4ff3994f4c..93f3951ad8 100644
--- a/phpBB/includes/functions_download.php
+++ b/phpBB/includes/functions_download.php
@@ -56,7 +56,7 @@ function send_avatar_to_browser($file, $browser)
 
 			if (strpos(strtolower($browser), 'msie 6.0') !== false)
 			{
-				header('Expires: -1');
+				header('Expires: ' . gmdate('D, d M Y H:i:s \G\M\T', time()));
 			}
 			else
 			{
@@ -197,7 +197,7 @@ function send_file_to_browser($attachment, $upload_dir, $category)
 			header('Content-Disposition: attachment; ' . header_filename(htmlspecialchars_decode($attachment['real_filename'])));
 			if (empty($user->browser) || (strpos(strtolower($user->browser), 'msie 6.0') !== false))
 			{
-				header('expires: -1');
+				header('Expires: ' . gmdate('D, d M Y H:i:s \G\M\T', time()));
 			}
 		}
 		else
diff --git a/phpBB/install/index.php b/phpBB/install/index.php
index 2e497da3db..7a2322629f 100644
--- a/phpBB/install/index.php
+++ b/phpBB/install/index.php
@@ -445,7 +445,7 @@ class module
 
 		header('Content-type: text/html; charset=UTF-8');
 		header('Cache-Control: private, no-cache="set-cookie"');
-		header('Expires: 0');
+		header('Expires: ' . gmdate('D, d M Y H:i:s \G\M\T', time()));
 		header('Pragma: no-cache');
 
 		return;