BCUninstaller/Bulk-Crap-Uninstaller · error · ManagementException

Action failed with return value {outParams["ReturnValue"]}.

Error message

Action failed with return value {outParams["ReturnValue"]}. Check return codes of Win32_Service class methods for more information.

What it means

The catch-all branch in CheckReturnValue: the WMI ReturnValue is non-zero, not 2 (Access Denied), and not in the ignoredCodes list (e.g. 16 'Marked For Deletion'), so it throws a System.Management.ManagementException with the raw return value and a hint to consult the Win32_Service return-code documentation. Every other failure mode (service not found, dependency running, etc.) lands here.

Source

Thrown at source/UninstallTools/Startup/Service/ServiceEntryFactory.cs:123

            var classInstance = GetServiceObject(serviceName);

            // Execute the method and obtain the return values.
            var outParams = classInstance.InvokeMethod("Delete", null, new InvokeMethodOptions { Timeout = TimeSpan.FromMinutes(1) });
            CheckReturnValue(outParams, 16); // 16 - Service Marked For Deletion
        }

        private static void CheckReturnValue(ManagementBaseObject outParams, params UInt32[] ignoredCodes)
        {
            if (outParams == null) return;

            var exitCode = (UInt32)outParams["ReturnValue"];
            if (exitCode == 0 || ignoredCodes.Any(x => x == exitCode)) return;

            if (exitCode == 2) // 2 - Access Denied
                throw new SecurityException("The user does not have the necessary access.");

            throw new ManagementException("Action failed with return value " + outParams["ReturnValue"] +
                ". Check return codes of Win32_Service class methods for more information.");
        }

        private static ManagementObject GetServiceObject(string serviceName)
        {
            return new ManagementObject("root\\CIMV2",
                $"Win32_Service.Name='{serviceName}'", new ObjectGetOptions { Timeout = TimeSpan.FromMinutes(1) });
        }
    }
}

View on GitHub (pinned to 608321de98)

Solutions

1. Inspect the numeric ReturnValue in the exception message and look it up in the Win32_Service.Create/Delete/StopService return-code table to identify the specific condition.
2. Stop dependent services first (and disable recovery) before deleting/stopping.
3. Catch ManagementException, decode the ReturnValue, and either retry with dependencies resolved or report the specific condition to the user.

Example fix

// before
ServiceEntryFactory.Delete(serviceEntry);

// after
try { ServiceEntryFactory.Delete(serviceEntry); }
catch (ManagementException ex)
{
    // ex.Message contains '...return value <N>'. Decode N per Win32_Service docs.
    logger.Error($"Service op failed: {ex.Message}");
    if (IsDependencyFailure(ex)) StopDependentsFirst(serviceEntry);
}

null

null

try { ServiceEntryFactory.Delete(serviceEntry); }
catch (ManagementException ex)
{
    var code = ExtractReturnValue(ex.Message);
    switch (code)
    {
        case 14: /* disabled */ EnableService(serviceEntry); ServiceEntryFactory.Delete(serviceEntry); break;
        case 9:  /* not found */ logger.Warn("Service already gone."); break;
        default: throw;
    }
}

When it happens

Trigger: Any WMI service operation that returns a non-zero code other than the ignored set — e.g. ReturnValue 7 'Service dependency deleted/failed', 8 'Service cannot start', 9 'Service not found', 14 'Service disabled', or the dependency-stop path returning a non-OK code.

Common situations: Trying to delete a service that has running dependencies; stopping a service whose recovery policy restarts it immediately; the service was already removed by another tool (code 9); the service is disabled (code 14).

Related errors

• The user does not have the necessary access.
• Win32_Directory.Compress returned {ret}
• Error while collecting Windows Features. If Windows Update i
• WMI query has hung while collecting Windows Features, try re

AI-assisted analysis of BCUninstaller/Bulk-Crap-Uninstaller@608321de98 (2026-08-13). Data as JSON: /api/errors/499d0617360af9d5. Report an issue: GitHub.