diff --git a/lib/Utils/API/Upload.php b/lib/Utils/API/Upload.php
index 02269aabb7..8bf8c1778e 100644
--- a/lib/Utils/API/Upload.php
+++ b/lib/Utils/API/Upload.php
@@ -191,7 +191,7 @@ protected function _uploadFile( $fileUp ) {
                 if ( !$this->_isRightMime( $fileUp ) ) {
                     $this->setObjectErrorOrThrowException(
                             $fileUp,
-                            new Exception ( __METHOD__ . " -> Mime type Not Allowed. '" . $out_filename . "'" )
+                            new Exception ( __METHOD__ . " -> File format not supported. '" . $out_filename . "'" )
                     );
                 }
 
diff --git a/lib/View/fileupload/upload.class.php b/lib/View/fileupload/upload.class.php
index 5a720f71b9..3e573a8a13 100644
--- a/lib/View/fileupload/upload.class.php
+++ b/lib/View/fileupload/upload.class.php
@@ -156,7 +156,7 @@ protected function validate( $uploaded_file, $file, $error, $index ) {
 
         if ( $file->type !== null ) {
             if ( !$this->_isRightMime( $file ) && ( !isset( $file->error ) || empty( $file->error ) ) ) {
-                $file->error = "Mime type Not Allowed";
+                $file->error = "File format not supported";
 
                 return false;
             }
diff --git a/public/css/sass/upload-page.scss b/public/css/sass/upload-page.scss
index 35e38c838a..3283d4a80a 100644
--- a/public/css/sass/upload-page.scss
+++ b/public/css/sass/upload-page.scss
@@ -1,3 +1,5 @@
+@import "commons/colors";
+
 body {
   margin: 0;
   padding: 0;
@@ -1082,6 +1084,10 @@ tr.ready .size span {
   visibility: visible;
 }
 
+.file_upload_error {
+  color: $redDefault;
+}
+
 .more {
   margin-bottom: 5px;
   float: left;