diff --git a/homeassistant/components/notify/file.py b/homeassistant/components/notify/file.py
index 3e2f20707ad..ec79cab59ea 100644
--- a/homeassistant/components/notify/file.py
+++ b/homeassistant/components/notify/file.py
@@ -54,7 +54,6 @@ class FileNotificationService(BaseNotificationService):
 
             if self.add_timestamp:
                 text = '{} {}\n'.format(dt_util.utcnow().isoformat(), message)
-                file.write(text)
             else:
                 text = '{}\n'.format(message)
-                file.write(text)
+            file.write(text)
diff --git a/homeassistant/components/notify/smtp.py b/homeassistant/components/notify/smtp.py
index 9ac73a49e3d..60fccc0c510 100644
--- a/homeassistant/components/notify/smtp.py
+++ b/homeassistant/components/notify/smtp.py
@@ -28,10 +28,10 @@ CONF_DEBUG = 'debug'
 CONF_SERVER = 'server'
 
 PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend({
-    vol.Required(CONF_RECIPIENT): cv.string,
+    vol.Required(CONF_RECIPIENT): vol.Email,
     vol.Optional(CONF_SERVER, default='localhost'): cv.string,
     vol.Optional(CONF_PORT, default=25): cv.port,
-    vol.Optional(CONF_SENDER): cv.string,
+    vol.Optional(CONF_SENDER): vol.Email,
     vol.Optional(CONF_STARTTLS, default=False): cv.boolean,
     vol.Optional(CONF_USERNAME): cv.string,
     vol.Optional(CONF_PASSWORD): cv.string,
diff --git a/homeassistant/helpers/config_validation.py b/homeassistant/helpers/config_validation.py
index d9c761832dc..c9a6917bb01 100644
--- a/homeassistant/helpers/config_validation.py
+++ b/homeassistant/helpers/config_validation.py
@@ -1,5 +1,6 @@
 """Helpers for config validation using voluptuous."""
 from datetime import timedelta
+import os
 from urllib.parse import urlparse
 
 from typing import Any, Union, TypeVar, Callable, Sequence, List, Dict
@@ -65,9 +66,17 @@ def boolean(value: Any) -> bool:
     return bool(value)
 
 
-def isfile(value):
+def isfile(value: Any) -> str:
     """Validate that the value is an existing file."""
-    return vol.IsFile('not a file')(value)
+    if value is None:
+        raise vol.Invalid('None is not file')
+    file_in = str(value)
+
+    if not os.path.isfile(file_in):
+        raise vol.Invalid('not a file')
+    if not os.access(file_in, os.R_OK):
+        raise vol.Invalid('file not readable')
+    return file_in
 
 
 def ensure_list(value: Union[T, Sequence[T]]) -> List[T]:
diff --git a/tests/components/camera/test_local_file.py b/tests/components/camera/test_local_file.py
index c30f59968e8..546152b0d8a 100644
--- a/tests/components/camera/test_local_file.py
+++ b/tests/components/camera/test_local_file.py
@@ -59,7 +59,7 @@ class TestLocalCamera(unittest.TestCase):
             fp.flush()
 
             with mock.patch('os.access', return_value=False):
-                assert setup_component(self.hass, 'camera', {
+                assert not setup_component(self.hass, 'camera', {
                     'camera': {
                         'name': 'config_test',
                         'platform': 'local_file',
diff --git a/tests/helpers/test_config_validation.py b/tests/helpers/test_config_validation.py
index 14d80d9104d..637d5ead0b7 100644
--- a/tests/helpers/test_config_validation.py
+++ b/tests/helpers/test_config_validation.py
@@ -1,4 +1,6 @@
 from datetime import timedelta
+import os
+import tempfile
 
 import pytest
 import voluptuous as vol
@@ -59,6 +61,24 @@ def test_port():
         schema(value)
 
 
+def test_isfile():
+    """Validate that the value is an existing file."""
+    schema = vol.Schema(cv.isfile)
+
+    with tempfile.NamedTemporaryFile() as fp:
+        pass
+
+    for value in ('invalid', None, -1, 0, 80000, fp.name):
+        with pytest.raises(vol.Invalid):
+            schema(value)
+
+    with tempfile.TemporaryDirectory() as tmp_path:
+        tmp_file = os.path.join(tmp_path, "test.txt")
+        with open(tmp_file, "w") as tmp_handl:
+            tmp_handl.write("test file")
+        schema(tmp_file)
+
+
 def test_url():
     """Test URL."""
     schema = vol.Schema(cv.url)