diff --git a/src/GitHub.Api/IO/NiceIO.cs b/src/GitHub.Api/IO/NiceIO.cs
index 9148466e6..263380592 100644
--- a/src/GitHub.Api/IO/NiceIO.cs
+++ b/src/GitHub.Api/IO/NiceIO.cs
@@ -62,7 +62,7 @@ private static StringComparison PathStringComparison
         public NPath(string path)
         {
             if (path == null)
-                throw new ArgumentNullException();
+                throw new ArgumentNullException("path");
 
             path = ParseDriveLetter(path, out _driveLetter);