diff --git a/keyserver/src/user/login.js b/keyserver/src/user/login.js
--- a/keyserver/src/user/login.js
+++ b/keyserver/src/user/login.js
@@ -146,6 +146,14 @@
       return identity_info;
     } catch (err) {
       console.warn('Failed to register user: ' + getMessageForException(err));
+      if (userInfo.usingIdentityCredentials === true) {
+        console.warn(
+          'Please restart nix and provide new user credentials',
+          '\nFor keyservers running in the Docker, set different',
+          'user credentials in COMM_JSONCONFIG_secrets_user_credentials,',
+          'remove all tables from the database, and restart',
+        );
+      }
       throw new ServerError('identity_auth_failed');
     }
   }