diff --git a/mayan/apps/dependencies/classes.py b/mayan/apps/dependencies/classes.py
index 07d1ebf105..c1bc790682 100644
--- a/mayan/apps/dependencies/classes.py
+++ b/mayan/apps/dependencies/classes.py
@@ -415,10 +415,14 @@ class Dependency(object):
         for replace_entry in replace_list or []:
             for path_entry in path_object.glob('**/{}'.format(replace_entry['filename_pattern'])):
                 if path_entry.is_file():
-                    with fileinput.FileInput(path_entry, inplace=True, backup='.bck') as fo:
-                        for line in fo:
-                            for pattern in replace_entry['content_patterns']:
-                                print(line.replace(pattern['search'], pattern['replace']), end='')
+                    # PY3
+                    # Don't use context processor to allow working on Python 2.7
+                    # Update on Mayan EDMS version >= 4.0
+                    file_object = fileinput.FileInput(force_text(path_entry), inplace=True)
+                    for line in file_object:
+                        for pattern in replace_entry['content_patterns']:
+                            print(line.replace(pattern['search'], pattern['replace']), end='')
+                    file_object.close()
 
     def verify(self):
         """
diff --git a/mayan/apps/dependencies/tests/test_classes.py b/mayan/apps/dependencies/tests/test_classes.py
index a43decfb52..dbc9f6ff87 100644
--- a/mayan/apps/dependencies/tests/test_classes.py
+++ b/mayan/apps/dependencies/tests/test_classes.py
@@ -25,7 +25,7 @@ class DependencyClassTestCase(BaseTestCase):
         path_temporary_directory = Path(temporary_directory)
         path_test_file = path_temporary_directory / 'test_file.css'
 
-        with open(path_test_file, mode='w') as file_object:
+        with path_test_file.open(mode='w') as file_object:
             file_object.write(
                 '@import url("https://fonts.googleapis.com/css?family=Lato:400,700,400italic");'
             )
@@ -45,7 +45,7 @@ class DependencyClassTestCase(BaseTestCase):
 
         dependency.patch_files(path=temporary_directory, replace_list=replace_list)
 
-        with open(path_test_file, mode='r') as file_object:
+        with path_test_file.open(mode='r') as file_object:
             final_text = file_object.read()
 
         shutil.rmtree(temporary_directory, ignore_errors=True)