diff --git a/setup/config/config_global.go b/setup/config/config_global.go
index 5b4ccf400..3234dadb4 100644
--- a/setup/config/config_global.go
+++ b/setup/config/config_global.go
@@ -114,6 +114,11 @@ func (c *Global) Verify(configErrs *ConfigErrors) {
 	checkNotEmpty(configErrs, "global.server_name", string(c.ServerName))
 	checkNotEmpty(configErrs, "global.private_key", string(c.PrivateKeyPath))
 
+	// Check that client well-known has a proper format
+	if c.WellKnownClientName != "" && !strings.HasPrefix(c.WellKnownClientName, "http://") && !strings.HasPrefix(c.WellKnownClientName, "https://") {
+		configErrs.Add("The configuration for well_known_client_name does not have a proper format, consider adding http:// or https://. Some clients may fail to connect.")
+	}
+
 	for _, v := range c.VirtualHosts {
 		v.Verify(configErrs)
 	}
diff --git a/setup/config/config_test.go b/setup/config/config_test.go
index 8a65c990f..eeefb425f 100644
--- a/setup/config/config_test.go
+++ b/setup/config/config_test.go
@@ -54,7 +54,7 @@ global:
   key_id: ed25519:auto
   key_validity_period: 168h0m0s
   well_known_server_name: "localhost:443"
-  well_known_client_name: "localhost:443"
+  well_known_client_name: "https://localhost"
   trusted_third_party_id_servers:
   - matrix.org
   - vector.im