diff --git a/O365/__init__.py b/O365/__init__.py
index <HASH>..<HASH> 100644
--- a/O365/__init__.py
+++ b/O365/__init__.py
@@ -1,6 +1,8 @@
 """
 A simple python library to interact with Microsoft Graph and Office 365 API
 """
+import warnings
+
 from .__version__ import __version__
 from .account import Account
 from .address_book import AddressBook, Contact, RecipientType
@@ -17,3 +19,7 @@ from .planner import Planner, Task
 from .utils import ImportanceLevel, Query, Recipient
 from .utils import OneDriveWellKnowFolderNames, OutlookWellKnowFolderNames
 from .utils import FileSystemTokenBackend, FirestoreBackend
+
+
+# allow Deprecation warnings to appear
+warnings.simplefilter('always', DeprecationWarning)
diff --git a/O365/connection.py b/O365/connection.py
index <HASH>..<HASH> 100644
--- a/O365/connection.py
+++ b/O365/connection.py
@@ -384,6 +384,13 @@ class Connection:
         :rtype: str
         """
 
+        # TODO: remove this warning in future releases
+        if redirect_uri == OAUTH_REDIRECT_URL:
+            warnings.warn('The default redirect uri was changed in version 1.1.4. to'
+                          ' "https://login.microsoftonline.com/common/oauth2/nativeclient".'
+                          ' You may have to change the registered app "redirect uri" or pass here the old "redirect_uri"',
+                          DeprecationWarning)
+
         client_id, client_secret = self.auth
 
         if requested_scopes:
DeprecationWarnings should now be printed out