Some mime types are wrapped with " which breaks file type checking. This will remove any wrapping \ and "
diff --git a/system/libraries/Upload.php b/system/libraries/Upload.php
index b85663b..7510449 100644
--- a/system/libraries/Upload.php
+++ b/system/libraries/Upload.php
@@ -190,7 +190,7 @@
$this->file_name = $this->_prep_filename($_FILES[$field]['name']);
$this->file_size = $_FILES[$field]['size'];
$this->file_type = preg_replace("/^(.+?);.*$/", "\\1", $_FILES[$field]['type']);
- $this->file_type = strtolower($this->file_type);
+ $this->file_type = trim(stripslashes($this->file_type), '"');
$this->file_ext = $this->get_extension($_FILES[$field]['name']);
// Convert the file size to kilobytes