chocolatey/choco · error · NotSupportedException

The '{0}' source does not support uninstalling packages

Error message

The '{0}' source does not support uninstalling packages

What it means

Thrown as a NotSupportedException when an uninstall operation against a non-normal source type returns null results. PerformSourceRunnerFunction<IUninstallSourceRunner> is called for alternative sources; if no runner implementing IUninstallSourceRunner is registered for the given SourceType, it returns default (null) and this exception fires.

Source

Thrown at src/chocolatey/infrastructure.app/services/ChocolateyPackageService.cs:1267

                var environmentBefore = GetInitialEnvironment(config);

                ConcurrentDictionary<string, PackageResult> results;

                if (config.SourceType.IsEqualTo(SourceTypes.Normal))
                {
                    var action = new Action<PackageResult, ChocolateyConfiguration>(HandlePackageUninstall);
                    var beforeUninstallAction = new Action<PackageResult, ChocolateyConfiguration>(BeforeModifyAction);

                    results = _nugetService.Uninstall(config, action, beforeUninstallAction);
                }
                else
                {
                    results = PerformSourceRunnerFunction<IUninstallSourceRunner, ConcurrentDictionary<string, PackageResult>>(config, runner => runner.Uninstall(config, null));
                }

                if (results is null)
                {
                    throw new NotSupportedException("The '{0}' source does not support uninstalling packages".FormatWith(config.SourceType));
                }

                foreach (var result in results)
                {
                    packageUninstalls.GetOrAdd(result.Key, result.Value);
                }

                // not handled in the uninstall handler
                IEnumerable<GenericRegistryValue> environmentChanges;
                IEnumerable<GenericRegistryValue> environmentRemovals;
                LogEnvironmentChanges(config, environmentBefore, out environmentChanges, out environmentRemovals);
            }
            finally
            {
                var actionSummaryResult = ReportActionSummary(packageUninstalls, "uninstalled");
                if (actionSummaryResult.Failures != 0 && Environment.ExitCode == 0)
                {
                    Environment.ExitCode = 1;

View on GitHub (pinned to 0d5abdd10c)

Solutions

  1. Verify the alternative source runner implements IUninstallSourceRunner for your source type.
  2. For normal packages, do not set an alternative source type — uninstall uses the local package metadata store.
  3. For custom runners, implement IUninstallSourceRunner and register the runner in the DI container.
  4. If the source type does not support uninstall, remove the package through its native tool instead.

Example fix

// before: runner lacks uninstall interface
public class MyRunner : IAlternativeSourceRunner, IInstallSourceRunner { }

// after: add uninstall support
public class MyRunner : IAlternativeSourceRunner, IInstallSourceRunner, IUninstallSourceRunner
{
    public ConcurrentDictionary<string, PackageResult> Uninstall(
        ChocolateyConfiguration config,
        Action<PackageResult, ChocolateyConfiguration> continueAction,
        Action<PackageResult, ChocolateyConfiguration> beforeUninstallAction)
    {
        return new ConcurrentDictionary<string, PackageResult>();
    }
}
Defensive patterns

Strategy: validation

Validate before calling

// Verify a runner implementing IUninstallSourceRunner exists for the source type
if (!config.SourceType.IsEqualTo(SourceTypes.Normal))
{
    var runners = _containerResolver.ResolveAll<IUninstallSourceRunner>();
    if (!runners.Any(r => r.SourceType.IsEqualTo(config.SourceType)))
    {
        throw new InvalidOperationException($"No uninstall runner registered for source type '{config.SourceType}'.");
    }
}

Type guard

public static bool SourceTypeSupportsUninstall(string sourceType, IEnumerable<IAlternativeSourceRunner> registeredRunners)
{
    if (sourceType.IsEqualTo(SourceTypes.Normal)) return true;
    return registeredRunners.OfType<IUninstallSourceRunner>().Any(r => r.SourceType.IsEqualTo(sourceType));
}

Try / catch

try
{
    _packageService.Uninstall(config);
}
catch (NotSupportedException ex) when (ex.Message.Contains("does not support uninstalling"))
{
    logger.Error($"Source type '{config.SourceType}' does not support uninstall. Use native tool or 'normal' source type.");
}

Prevention

When it happens

Trigger: Calling Uninstall with config.SourceType set to a non-normal value when no alternative source runner implementing IUninstallSourceRunner is registered. The null-check on results after the runner function call triggers the throw.

Common situations: Running 'choco uninstall pkg --source-type python' where the Python source runner does not implement IUninstallSourceRunner. Alternative source runners commonly support install but not uninstall.

Related errors

AI-assisted analysis of chocolatey/choco@0d5abdd10c (2026-08-13). Data as JSON: /api/errors/46a81344e8543447. Report an issue: GitHub.