diff --git a/m2r.py b/m2r.py
index a4e43c2..fad531a 100644
--- a/m2r.py
+++ b/m2r.py
@@ -10,8 +10,7 @@ from argparse import ArgumentParser, Namespace
 
 from docutils import statemachine, nodes, io, utils
 from docutils.parsers import rst
-from docutils.core import ErrorString
-from docutils.utils import SafeString, column_width
+from docutils.utils import column_width
 import mistune
 
 if sys.version_info < (3, ):
@@ -609,10 +608,10 @@ class MdInclude(rst.Directive):
             raise self.severe('Problems with "%s" directive path:\n'
                               'Cannot encode input file path "%s" '
                               '(wrong locale?).' %
-                              (self.name, SafeString(path)))
+                              (self.name, path))
         except IOError as error:
             raise self.severe('Problems with "%s" directive path:\n%s.' %
-                              (self.name, ErrorString(error)))
+                              (self.name, io.error_string(error)))
 
         # read from the file
         startline = self.options.get('start-line', None)
@@ -625,7 +624,7 @@ class MdInclude(rst.Directive):
                 rawtext = include_file.read()
         except UnicodeError as error:
             raise self.severe('Problem with "%s" directive:\n%s' %
-                              (self.name, ErrorString(error)))
+                              (self.name, io.error_string(error)))
 
         config = self.state.document.settings.env.config
         converter = M2R(