diff --git a/excel_import_export/models/common.py b/excel_import_export/models/common.py
index 3f5fc50fe..5e70f0d95 100644
--- a/excel_import_export/models/common.py
+++ b/excel_import_export/models/common.py
@@ -268,13 +268,12 @@ def _get_cell_value(cell, field_type=False):
     datemode = 0  # From book.datemode, but we fix it for simplicity
     if field_type in ['date', 'datetime']:
         ctype = xlrd.sheet.ctype_text.get(cell.ctype, 'unknown type')
-        if ctype == 'number':
+        if ctype in ('xldate', 'number'):
+            is_datetime = cell.value % 1 != 0.0
             time_tuple = xlrd.xldate_as_tuple(cell.value, datemode)
             date = dt(*time_tuple)
-            if field_type == 'date':
-                value = date.strftime("%Y-%m-%d")
-            elif field_type == 'datetime':
-                value = date.strftime("%Y-%m-%d %H:%M:%S")
+            value = (date.strftime("%Y-%m-%d %H:%M:%S")
+                     if is_datetime else date.strftime("%Y-%m-%d"))
         else:
             value = cell.value
     elif field_type in ['integer', 'float']:
diff --git a/excel_import_export/models/xlsx_import.py b/excel_import_export/models/xlsx_import.py
index 933d86149..389a0a544 100644
--- a/excel_import_export/models/xlsx_import.py
+++ b/excel_import_export/models/xlsx_import.py
@@ -203,14 +203,19 @@ class XLSXImport(models.AbstractModel):
                  'encoding': '',
                  'separator': '',
                  'quoting': '"',
-                 'date_style': '',
-                 'datetime_style': '%Y-%m-%d %H:%M:%S',
+                 'date_format': '%Y-%m-%d',
+                 'datetime_format': '%Y-%m-%d %H:%M:%S',
                  'float_thousand_separator': ',',
                  'float_decimal_separator': '.',
                  'fields': []})
             if errors.get('messages'):
-                message = errors['messages']['message'].encode('utf-8')
-                raise ValidationError(message)
+                message = _('Error importing data')
+                messages = errors['messages']
+                if isinstance(messages, dict):
+                    message = messages['message']
+                if isinstance(messages, list):
+                    message = ', '.join([x['message'] for x in messages])
+                raise ValidationError(message.encode('utf-8'))
             return self.env.ref(xml_id)
         except xlrd.XLRDError:
             raise ValidationError(