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Reboot Pending Prompt - Detection

Overview

This script serves as the detection logic for the Reboot Pending Prompt solution. Its primary function is to intelligently decide whether a reboot prompt should be displayed to the user.

It performs checks in three key areas:

  1. Operational Safety: Before evaluating necessity, the script checks if the Reboot Pending prompt - Autofix is currently active (specifically checking for the scheduled task it manages). If a prompt cycle is already in progress, this script exits immediately to prevent conflicting or duplicate actions.
  2. Necessity: It determines if a reboot is actually required by checking Windows Registry keys (for pending updates), comparing system uptime against a configured threshold, or checking for a manual administrator override.
  3. Timing & Convenience: If a reboot is needed, the script then validates if the current moment is appropriate for a prompt. It checks constraints such as "Quiet Hours" (suppress windows), weekend exclusions, user presence (logged in vs. lock screen), and ensures the user isn't prompted too frequently.

If the script determines a reboot is needed, the timing is valid, and no conflicting prompts are active, it returns an exit code that triggers the remediation script.

Install-In-Progress Protection

Before allowing any unattended reboot (no user logged in, or locked screen with the missed prompt threshold reached), the script checks whether the machine is currently installing software or updates. If it detects an active install, it skips the reboot and exits cleanly. The next time the script runs, it checks again. Once the install finishes, the reboot proceeds normally.

This prevents the machine from restarting in the middle of a Windows Update, application installer, or feature upgrade.

The script looks for the following signals:

SignalWhat It Means
TiWorker.exeWindows Update is actively installing an update
wusa.exeA standalone Windows Update package is being installed
SetupHost.exeA Windows Feature Update is in progress
setup.exeA general installer is running
MoUsoCoreWorker.exeThe Windows Update orchestrator is doing background work
Windows10Upgrader.exeA feature upgrade using the Windows Update Agent is running
winget.exe (active)Windows Package Manager is installing or updating software (only when actively using CPU)
BITS transfer jobsBackground downloads are in progress (used by Windows Update and other services)
MSI mutex heldAn MSI installer package is currently running

Note: This check only applies to unattended reboots. If a user is at their desk and clicks "Yes" to reboot, the reboot happens immediately regardless of background installs. The user made a conscious choice.

Sample Run

Note: This script is specifically engineered to operate as the detection condition within the Reboot Pending Prompt - Windows Workstation policy. Manual execution is not recommended, as the script's output is intended to trigger automated remediation actions rather than provide direct feedback.

Dependencies

Custom Fields

Custom FieldDescription
cPVAL Pending RebootManual override to force a prompt cycle.
cPVAL Last PromptedTimestamp of the last successful prompt. Managed automatically.
cPVAL Times PromptedCounter for how many times the user has been prompted. Managed automatically.
cPVAL Reboot Prompt When Pending RebootEnable/Disable detection based on Windows Registry keys.
cPVAL Reboot Prompt Uptime DaysUptime threshold (days) to trigger a reboot. Set to 0 to disable.
cPVAL Reboot Prompt CountMax number of prompts allowed before the cycle resets (or force reboot occurs).
cPVAL Reboot Prompt Duration Between PromptMinimum hours to wait between consecutive prompts.
cPVAL Reboot Prompt Skip WeekendsEnable to suppress prompts on Saturdays and Sundays.
cPVAL Reboot Prompt Suppress Time Window24-hour time range (HHmm-HHmm) to suppress prompts (e.g., '1800-0800').
cPVAL Reboot if Not Logged InEnable to reboot immediately if no user is signed in.
cPVAL Max Missed Prompts Before ForceNumber of consecutive missed prompts allowed before the script triggers a forced reboot. Set to 0 to disable forced reboot.
cPVAL Consecutive Missed PromptsTracks how many prompt cycles were missed because the screen was locked or no user was signed in. Managed automatically.
cPVAL First Missed Prompt TimeRecords when the current missed-prompt streak began. Managed automatically.

Default Values

The script includes built-in defaults when related custom fields are blank or not set:

SettingVariable NameDefault Value
Reboot Prompt Count$defaultRegularPromptCount4
Reboot Prompt Duration Between Prompt$defaultDurationBetweenPromptsHours4 hours
Reboot Prompt Suppress Time Window$defaultSuppressTimeWindowBlank (disabled)
Max Missed Prompts Before Force$defaultMaxMissedPromptsBeforeForce0 (disabled)
Reboot if Not Logged In$defaultRebootIfNotLoggedInDisable
Reboot Prompt Skip Weekends$defaultSkipWeekendsDisable

Do not change these values directly in the script. The PowerShell script is code-signed, and editing the defaults will break the signature. If you need different built-in defaults, send a request to ProVal.

Automation Setup/Import

Automation Configuration

Output

  • Activity Details: Text output indicating if a reboot is required and if conditions were met.
  • Custom Fields: Updates cPVAL Pending Reboot, cPVAL Last Prompted, cPVAL Times Prompted, cPVAL Consecutive Missed Prompts, and cPVAL First Missed Prompt Time as part of reset and missed-prompt tracking.

Changelog

2026-06-10

  • Missed prompt counter now uses real elapsed time instead of counting each script run. This makes the forced reboot timeline predictable no matter how often the detection script checks in.
  • Added safety checks for active installations before rebooting unattended machines. The script now looks for Windows Updates, feature upgrades, MSI installers, BITS downloads, and winget activity.
  • If a forced reboot is due but an install is still running, the reboot waits until the install finishes. It will trigger automatically on the next check after the install completes.
  • Machines with no user logged in will no longer reboot mid-update. The script exits safely and retries on the next cycle once servicing is done.
  • Winget (Windows Package Manager) is only treated as active when it is actually doing work, preventing false detections from an idle process.
  • Script documentation updated to reflect all of the above changes.

2026-06-03

  • Added support for missed-prompt tracking custom fields.
  • Added default values for missed-prompt handling, weekend behavior, suppress window behavior, and no-user reboot behavior.

2026-05-26

  • Added a default values region in the PowerShell script.
  • Fixed a bug where the script was failing to reset the custom fields for manual reboot after rejecting the first prompt.

2026-03-23

  • Updated .Net8 Desktop Runtime installation logic to install the latest available version.
  • Code Signed the PowerShell script.

2025-12-19

  • Initial version of the document