diff --git a/zerver/tests/test_push_notifications.py b/zerver/tests/test_push_notifications.py
index cdc8127785..96b0b03659 100644
--- a/zerver/tests/test_push_notifications.py
+++ b/zerver/tests/test_push_notifications.py
@@ -2663,7 +2663,7 @@ class PushBouncerSignupTest(ZulipTestCase):
         result = self.client_post("/api/v1/remotes/server/register", request)
         self.assert_json_error(
             result,
-            "Invalid server administrator email address: Invalid email address.",
+            "Invalid server administrator email address: example.com is not a valid email domain.",
         )
 
         # An example disposable domain.
diff --git a/zilencer/views.py b/zilencer/views.py
index bb1bffdf4c..418aa8bda9 100644
--- a/zilencer/views.py
+++ b/zilencer/views.py
@@ -245,7 +245,7 @@ def register_remote_server(
 
     contact_email_domain = Address(addr_spec=contact_email).domain.lower()
     if contact_email_domain == "example.com":
-        raise ServerAdminEmailError(_("Invalid email address."))
+        raise ServerAdminEmailError(_("example.com is not a valid email domain."))
 
     # Check if the domain has an MX record
     resolver = dns_resolver.Resolver()