diff --git a/application/config/mimes.php b/application/config/mimes.php
index 5b8ceff..6ff3812 100644
--- a/application/config/mimes.php
+++ b/application/config/mimes.php
@@ -58,7 +58,7 @@
 	'mif'	=>	'application/vnd.mif',
 	'xls'	=>	array('application/vnd.ms-excel', 'application/msexcel', 'application/x-msexcel', 'application/x-ms-excel', 'application/x-excel', 'application/x-dos_ms_excel', 'application/xls', 'application/x-xls', 'application/excel', 'application/download', 'application/vnd.ms-office', 'application/msword'),
 	'ppt'	=>	array('application/powerpoint', 'application/vnd.ms-powerpoint'),
-	'pptx'	=> 	'application/vnd.openxmlformats-officedocument.presentationml.presentation',
+	'pptx'	=> 	array('application/vnd.openxmlformats-officedocument.presentationml.presentation', 'application/x-zip', 'application/zip'),
 	'wbxml'	=>	'application/wbxml',
 	'wmlc'	=>	'application/wmlc',
 	'dcr'	=>	'application/x-director',
@@ -126,7 +126,7 @@
 	'docx'	=>	array('application/vnd.openxmlformats-officedocument.wordprocessingml.document', 'application/zip', 'application/msword', 'application/x-zip'),
 	'dot'	=>	array('application/msword', 'application/vnd.ms-office'),
 	'dotx'	=>	array('application/vnd.openxmlformats-officedocument.wordprocessingml.document', 'application/zip', 'application/msword'),
-	'xlsx'	=>	array('application/vnd.openxmlformats-officedocument.spreadsheetml.sheet', 'application/zip', 'application/vnd.ms-excel', 'application/msword'),
+	'xlsx'	=>	array('application/vnd.openxmlformats-officedocument.spreadsheetml.sheet', 'application/zip', 'application/vnd.ms-excel', 'application/msword', 'application/x-zip'),
 	'word'	=>	array('application/msword', 'application/octet-stream'),
 	'xl'	=>	'application/excel',
 	'eml'	=>	'message/rfc822',