diff --git a/src/libraries/System.Net.Http/tests/FunctionalTests/NtAuthTests.cs b/src/libraries/System.Net.Http/tests/FunctionalTests/NtAuthTests.cs
index 0a13042fc33d5..d8662fd4a4e15 100644
--- a/src/libraries/System.Net.Http/tests/FunctionalTests/NtAuthTests.cs
+++ b/src/libraries/System.Net.Http/tests/FunctionalTests/NtAuthTests.cs
@@ -167,7 +167,7 @@ public async Task PostAsync_NtAuthServer_UseExpect100Header_Success(bool ntlm, i
         public async Task AuthTest(string authType)
         {
             var testUri = new Uri("http://emclientntlm.westus.cloudapp.azure.com/");
-            var networkCredential = new NetworkCredential("user1", "PLACEHOLDERcorrect20", "emclientntlm");
+            var networkCredential = new NetworkCredential("user1", "PLACEHOLDERcorrect20", "emclientntlm.westus.cloudapp.azure.com");
 
             using var socketsHandler = new SocketsHttpHandler();
             var credentialCache = new CredentialCache();