Azure DevOps: Obsolete TFVC policies warning cannot be resolved - policies not visible in Visual Studio or tf.exe

Hello Daniel,

The reason you are unable to save new policies and keep getting the warning is that Azure DevOps blocks any configuration saves when it detects a mix of obsolete and new policies. Because the obsolete policies are hidden from the current Visual Studio UI and cannot be deleted from there, your project is essentially stuck in a state where the legacy policies block any check-ins and edits.

As you noticed, the REST API (/_apis/policy/configurations) is strictly for Git branch policies, and tf.exe does not have an active policy management command to solve this.

To clear these hidden obsolete policies, you will need to run a small C# application using the legacy TFVC client API. Once they are cleared, the Check-in Policies tab will properly register new built-in policies without warnings.

Here are the exact steps and code to remove the deprecated policy metadata:

1. Create a new C# Console App (.NET Framework 4.8) in Visual Studio. (Note: Do not use .NET Core / .NET 5+ as the legacy client Object Model requires .NET Framework).
2. Install the following NuGet package: Microsoft.TeamFoundationServer.ExtendedClient (v19.x or latest).
3. Use the following code in your Program.cs. Replace {UrlToYourCollection} (e.g., https://dev.azure.com/yourorg) and {YourProjectName} with your specific details:

      using System;
      using Microsoft.TeamFoundation.Client;
      using Microsoft.TeamFoundation.VersionControl.Client;
      
      namespace ClearTFVCPolicies
      {
          class Program
          {
              static void Main(string[] args)
              {
                  var collectionUri = "{UrlToYourCollection}";
                  var currentProjectName = "{YourProjectName}";
   
                  using (TfsTeamProjectCollection tpc = new TfsTeamProjectCollection(new Uri(collectionUri)))
                  {
                      // Authenticate and get the Version Control Server
                      var versionControlServer = tpc.GetService<VersionControlServer>();
                   
                      // Get the specific Team Project
                      TeamProject teamProject = versionControlServer.GetTeamProject(currentProjectName);
                   
                      // Clear the obsolete policies by setting them to null
                      teamProject.SetCheckinPolicies(null);
                   
                      Console.WriteLine("Obsolete check-in policies have been successfully cleared.");
                      Console.ReadLine();
                  }
              }
          }
      }
   

Note: You must be a Project Administrator to successfully run this script.

Once you run this code, restart Visual Studio, go back into Team Explorer -> Settings -> Source Control -> Check-in Policy, and you will now be able to add the updated policies without receiving the warning.

Reference: TFVC check-in policy migrate guide - Remove existing obsolete policies

Note: This response is drafted with the help of AI systems.