peass-ng/PEASS-ng · error · NotV1SupportedException

This LogonType is not supported on Task Scheduler 1.0.

Error message

This LogonType is not supported on Task Scheduler 1.0.

What it means

V1 capability check in RegisterTaskDefinition: when running against Task Scheduler 1.0 (pre-Vista OS), the requested TaskCreation value (e.g. validation-only or security-related options like ValidateOnly/DontAddPrincipalAce equivalents) has no equivalent in the legacy API, so the guard throws NotV1SupportedException rather than silently mis-registering the task.

Source

Thrown at winPEAS/winPEASexe/winPEAS/TaskScheduler/TaskFolder.cs:532

            }

            // Check for V1 invalid task names
            string invChars = Regex.Escape(new string(System.IO.Path.GetInvalidFileNameChars()));
            if (Regex.IsMatch(path, @"[" + invChars + @"]"))
                throw new ArgumentOutOfRangeException(nameof(path), @"Task names may not include any characters which are invalid for file names.");
            if (Regex.IsMatch(path, @"\.[^" + invChars + @"]{0,3}\z"))
                throw new ArgumentOutOfRangeException(nameof(path), @"Task names ending with a period followed by three or fewer characters cannot be retrieved due to a bug in the native library.");

            // Adds ability to set a password for a V1 task. Provided by Arcao.
            TaskFlags flags = definition.v1Task.GetFlags();
            if (logonType == TaskLogonType.InteractiveTokenOrPassword && string.IsNullOrEmpty(password))
                logonType = TaskLogonType.InteractiveToken;
            switch (logonType)
            {
                case TaskLogonType.Group:
                case TaskLogonType.S4U:
                case TaskLogonType.None:
                    throw new NotV1SupportedException("This LogonType is not supported on Task Scheduler 1.0.");
                case TaskLogonType.InteractiveToken:
                    flags |= (TaskFlags.RunOnlyIfLoggedOn | TaskFlags.Interactive);
                    definition.v1Task.SetAccountInformation(user.Name, IntPtr.Zero);
                    break;
                case TaskLogonType.ServiceAccount:
                    flags &= ~(TaskFlags.Interactive | TaskFlags.RunOnlyIfLoggedOn);
                    definition.v1Task.SetAccountInformation((String.IsNullOrEmpty(userId) || user.IsSystem) ? String.Empty : user.Name, IntPtr.Zero);
                    break;
                case TaskLogonType.InteractiveTokenOrPassword:
                    flags |= TaskFlags.Interactive;
                    using (CoTaskMemString cpwd = new CoTaskMemString(password))
                        definition.v1Task.SetAccountInformation(user.Name, cpwd.DangerousGetHandle());
                    break;
                case TaskLogonType.Password:
                    using (CoTaskMemString cpwd = new CoTaskMemString(password))
                        definition.v1Task.SetAccountInformation(user.Name, cpwd.DangerousGetHandle());
                    break;
                default:

View on GitHub (pinned to 53fb989abc)

Solutions

1. Use only TaskCreation.Create, CreateOrUpdate, Disable or Update when targeting Task Scheduler 1.0
2. Require or target Task Scheduler 2.0+ (Vista/Server 2008 and later) for advanced creation options

When it happens

Trigger: Thrown at winPEAS/winPEASexe/winPEAS/TaskScheduler/TaskFolder.cs:532 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of peass-ng/PEASS-ng@53fb989abc (2026-09-02). Data as JSON: /api/errors/730b2fa0eb0ab420. Report an issue: GitHub.