diff --git a/homeassistant/auth/providers/homeassistant.py b/homeassistant/auth/providers/homeassistant.py
index 4e38260dd2f..ec39bdbdcdc 100644
--- a/homeassistant/auth/providers/homeassistant.py
+++ b/homeassistant/auth/providers/homeassistant.py
@@ -55,13 +55,6 @@ class InvalidUser(HomeAssistantError):
     Will not be raised when validating authentication.
     """
 
-
-class InvalidUsername(InvalidUser):
-    """Raised when invalid username is specified.
-
-    Will not be raised when validating authentication.
-    """
-
     def __init__(
         self,
         *args: object,
@@ -77,6 +70,13 @@ class InvalidUsername(InvalidUser):
         )
 
 
+class InvalidUsername(InvalidUser):
+    """Raised when invalid username is specified.
+
+    Will not be raised when validating authentication.
+    """
+
+
 class Data:
     """Hold the user data."""
 
@@ -216,7 +216,7 @@ class Data:
                 break
 
         if index is None:
-            raise InvalidUser
+            raise InvalidUser(translation_key="user_not_found")
 
         self.users.pop(index)
 
@@ -232,7 +232,7 @@ class Data:
                 user["password"] = self.hash_password(new_password, True).decode()
                 break
         else:
-            raise InvalidUser
+            raise InvalidUser(translation_key="user_not_found")
 
     @callback
     def _validate_new_username(self, new_username: str) -> None:
@@ -275,7 +275,7 @@ class Data:
                 self._async_check_for_not_normalized_usernames(self._data)
                 break
         else:
-            raise InvalidUser
+            raise InvalidUser(translation_key="user_not_found")
 
     async def async_save(self) -> None:
         """Save data."""
diff --git a/homeassistant/components/auth/strings.json b/homeassistant/components/auth/strings.json
index 0e4cede78a3..c8622880f0f 100644
--- a/homeassistant/components/auth/strings.json
+++ b/homeassistant/components/auth/strings.json
@@ -37,7 +37,10 @@
       "message": "Username \"{username}\" already exists"
     },
     "username_not_normalized": {
-      "message": "Username \"{new_username}\" is not normalized"
+      "message": "Username \"{new_username}\" is not normalized. Please make sure the username is lowercase and does not contain any whitespace."
+    },
+    "user_not_found": {
+      "message": "User not found"
     }
   },
   "issues": {
diff --git a/homeassistant/components/config/auth_provider_homeassistant.py b/homeassistant/components/config/auth_provider_homeassistant.py
index 1cfcda6d4b2..8513c53bd07 100644
--- a/homeassistant/components/config/auth_provider_homeassistant.py
+++ b/homeassistant/components/config/auth_provider_homeassistant.py
@@ -53,11 +53,7 @@ async def websocket_create(
         )
         return
 
-    try:
-        await provider.async_add_auth(msg["username"], msg["password"])
-    except auth_ha.InvalidUser:
-        connection.send_error(msg["id"], "username_exists", "Username already exists")
-        return
+    await provider.async_add_auth(msg["username"], msg["password"])
 
     credentials = await provider.async_get_or_create_credentials(
         {"username": msg["username"]}
@@ -94,13 +90,7 @@ async def websocket_delete(
         connection.send_result(msg["id"])
         return
 
-    try:
-        await provider.async_remove_auth(msg["username"])
-    except auth_ha.InvalidUser:
-        connection.send_error(
-            msg["id"], "auth_not_found", "Given username was not found."
-        )
-        return
+    await provider.async_remove_auth(msg["username"])
 
     connection.send_result(msg["id"])
 
@@ -187,14 +177,8 @@ async def websocket_admin_change_password(
         )
         return
 
-    try:
-        await provider.async_change_password(username, msg["password"])
-        connection.send_result(msg["id"])
-    except auth_ha.InvalidUser:
-        connection.send_error(
-            msg["id"], "credentials_not_found", "Credentials not found"
-        )
-        return
+    await provider.async_change_password(username, msg["password"])
+    connection.send_result(msg["id"])
 
 
 @websocket_api.websocket_command(
diff --git a/tests/components/config/test_auth_provider_homeassistant.py b/tests/components/config/test_auth_provider_homeassistant.py
index ffee88f91ec..6b580013968 100644
--- a/tests/components/config/test_auth_provider_homeassistant.py
+++ b/tests/components/config/test_auth_provider_homeassistant.py
@@ -183,7 +183,13 @@ async def test_create_auth_duplicate_username(
 
     result = await client.receive_json()
     assert not result["success"], result
-    assert result["error"]["code"] == "username_exists"
+    assert result["error"] == {
+        "code": "home_assistant_error",
+        "message": "username_already_exists",
+        "translation_key": "username_already_exists",
+        "translation_placeholders": {"username": "test-user"},
+        "translation_domain": "auth",
+    }
 
 
 async def test_delete_removes_just_auth(
@@ -282,7 +288,13 @@ async def test_delete_unknown_auth(
 
     result = await client.receive_json()
     assert not result["success"], result
-    assert result["error"]["code"] == "auth_not_found"
+    assert result["error"] == {
+        "code": "home_assistant_error",
+        "message": "user_not_found",
+        "translation_key": "user_not_found",
+        "translation_placeholders": None,
+        "translation_domain": "auth",
+    }
 
 
 async def test_change_password(