diff --git a/server/src/domain/system-config/system-config.core.ts b/server/src/domain/system-config/system-config.core.ts
index ebcd57740aa1e..b3a030487a94d 100644
--- a/server/src/domain/system-config/system-config.core.ts
+++ b/server/src/domain/system-config/system-config.core.ts
@@ -328,7 +328,7 @@ export class SystemConfigCore {
         }
 
         if (!_.isEmpty(file)) {
-          throw new Error(`Unknown keys found: ${file}`);
+          throw new Error(`Unknown keys found: ${JSON.stringify(file)}`);
         }
 
         this.configCache = overrides;