diff --git a/electrum/gui/qt/installwizard.py b/electrum/gui/qt/installwizard.py
index 40b83c08d..ab53206d1 100644
--- a/electrum/gui/qt/installwizard.py
+++ b/electrum/gui/qt/installwizard.py
@@ -299,7 +299,7 @@ class InstallWizard(QDialog, MessageBoxMixin, BaseWizard):
         def run_user_interaction_loop():
             while True:
                 if self.loop.exec_() != 2:  # 2 = next
-                    raise UserCancelled
+                    raise UserCancelled()
                 assert temp_storage
                 if temp_storage.file_exists() and not temp_storage.is_encrypted():
                     break
@@ -423,7 +423,7 @@ class InstallWizard(QDialog, MessageBoxMixin, BaseWizard):
         self.set_layout(layout, title, next_enabled)
         result = self.loop.exec_()
         if not result and raise_on_cancel:
-            raise UserCancelled
+            raise UserCancelled()
         if result == 1:
             raise GoBack from None
         self.title.setVisible(False)
diff --git a/electrum/plugins/trezor/clientbase.py b/electrum/plugins/trezor/clientbase.py
index 3d83f5736..e7f1057b8 100644
--- a/electrum/plugins/trezor/clientbase.py
+++ b/electrum/plugins/trezor/clientbase.py
@@ -79,7 +79,7 @@ class TrezorClientBase(HardwareClientBase, Logger):
         self.end_flow()
         if e is not None:
             if isinstance(e, Cancelled):
-                raise UserCancelled from e
+                raise UserCancelled() from e
             elif isinstance(e, TrezorFailure):
                 raise RuntimeError(str(e)) from e
             elif isinstance(e, OutdatedFirmwareError):