diff --git a/eng/helix/content/RunTests/ProcessUtil.cs b/eng/helix/content/RunTests/ProcessUtil.cs
index 8c25f9fb5d..0ce0b2c571 100644
--- a/eng/helix/content/RunTests/ProcessUtil.cs
+++ b/eng/helix/content/RunTests/ProcessUtil.cs
@@ -98,7 +98,7 @@ namespace RunTests
                 Console.WriteLine($"'{process.StartInfo.FileName} {process.StartInfo.Arguments}' completed with exit code '{process.ExitCode}'");
                 if (throwOnError && process.ExitCode != 0)
                 {
-                    processLifetimeTask.TrySetException(new InvalidOperationException($"Command {filename} {arguments} returned exit code {process.ExitCode}"));
+                    processLifetimeTask.TrySetException(new InvalidOperationException($"Command {filename} {arguments} returned exit code {process.ExitCode} output: {outputBuilder.ToString()}"));
                 }
                 else
                 {
diff --git a/eng/helix/content/RunTests/TestRunner.cs b/eng/helix/content/RunTests/TestRunner.cs
index 92f6bf065a..65dd451036 100644
--- a/eng/helix/content/RunTests/TestRunner.cs
+++ b/eng/helix/content/RunTests/TestRunner.cs
@@ -120,22 +120,28 @@ namespace RunTests
 
                     await ProcessUtil.RunAsync($"{Options.DotnetRoot}/dotnet",
                         $"nuget add source {Options.HELIX_WORKITEM_ROOT} --configfile NuGet.config",
-                        environmentVariables: EnvironmentVariables);
+                        environmentVariables: EnvironmentVariables,
+                        outputDataReceived: Console.WriteLine,
+                        errorDataReceived: Console.Error.WriteLine);
 
                     await ProcessUtil.RunAsync($"{Options.DotnetRoot}/dotnet",
                         "nuget add source https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet5/nuget/v3/index.json --configfile NuGet.config",
-                        environmentVariables: EnvironmentVariables);
+                        environmentVariables: EnvironmentVariables,
+                        outputDataReceived: Console.WriteLine,
+                        errorDataReceived: Console.Error.WriteLine);
 
                     // Write nuget sources to console, useful for debugging purposes
                     await ProcessUtil.RunAsync($"{Options.DotnetRoot}/dotnet",
                         "nuget list source",
                         environmentVariables: EnvironmentVariables,
                         outputDataReceived: Console.WriteLine,
-                        errorDataReceived: Console.WriteLine);
+                        errorDataReceived: Console.Error.WriteLine);
 
                     await ProcessUtil.RunAsync($"{Options.DotnetRoot}/dotnet",
                         $"tool install dotnet-ef --global --version {Options.EfVersion}",
-                        environmentVariables: EnvironmentVariables);
+                        environmentVariables: EnvironmentVariables,
+                        outputDataReceived: Console.WriteLine,
+                        errorDataReceived: Console.Error.WriteLine);
 
                     // ';' is the path separator on Windows, and ':' on Unix
                     Options.Path += RuntimeInformation.IsOSPlatform(OSPlatform.Windows) ? ";" : ":";
@@ -219,7 +225,7 @@ namespace RunTests
                         commonTestArgs + " --TestCaseFilter:\"Quarantined=true\"",
                         environmentVariables: EnvironmentVariables,
                         outputDataReceived: Console.WriteLine,
-                        errorDataReceived: Console.WriteLine,
+                        errorDataReceived: Console.Error.WriteLine,
                         throwOnError: false);
 
                     if (result.ExitCode != 0)