diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index f3e4198b0dfa..1fcbcd944ab0 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -5,7 +5,7 @@
- Install Visual Studio 2022 (Community or higher) and make sure you have the latest updates (https://www.visualstudio.com/).
- Install the **.NET desktop development** workload in VisualStudio
- Need at least .NET Framework 4.6.2 and 4.7.1 development tools
-- Install **.NET 9.0.102 SDK** for your specific [platform](https://dotnet.microsoft.com/download). (or a higher version within the 9.0.*** band)
+- Install **.NET 9.0.306 SDK** for your specific [platform](https://dotnet.microsoft.com/download). (or a higher version within the 9.0.*** band)
- Install the latest version of git (https://git-scm.com/downloads)
- Install [PowerShell](https://docs.microsoft.com/powershell/scripting/install/installing-powershell), version 7 or higher, if you plan to make public API changes or are working with generated code snippets.
- Install [NodeJS](https://nodejs.org/) (22.x.x) if you plan to use [C# code generation](https://github.com/Azure/autorest.csharp).
@@ -306,6 +306,32 @@ You can add the dev feed to your NuGet.Config file, which can be at the Solution
> You can place a NuGet.Config file in the root of your solution. Projects within the solution will use the feed defined in that file.
+##### Unauthorized access to the feed
+
+If you are getting a 401 error, similar to `401 (Unauthorized - No local versions of package "xyz"; please provide authentication to access versions from upstream that have not yet been saved to your feed.)` it means you are trying
+to access a package version that is not on the feed but is on the upstream feed `nuget.org` and you don't have permissions to pull that version into the feed. There are two possible solutions to this issue:
+
+1. If you are a member of the team with access and want to update a version of the package in the feed you will need to authenticate to the feed. For local authentication you will want to use [Azure Artifacts Credential Provider](https://github.com/microsoft/artifacts-credprovider#azure-artifacts-credential-provider).
+ If you need to authenticate a pipeline in our teams DevOps org you will want login via the [NuGetAuthenticate](https://learn.microsoft.com/azure/devops/pipelines/tasks/package/nuget-authenticate?view=azure-devops#dotnet) task.
+1. If you are external user and just want to consume packages in the feed you can scope the packages for the feed to just the ones you want by using [packageSourceMapping](https://learn.microsoft.com/nuget/reference/nuget-config-file#packagesource) similar to:
+```xml
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+```
+
### 2. Find NuGet Package
You can use the following options to find the available dev feed packages:
diff --git a/NuGet.Config b/NuGet.Config
index fd5e01a14466..c679a5601f0e 100644
--- a/NuGet.Config
+++ b/NuGet.Config
@@ -2,8 +2,7 @@
-
-
+