Reboots machine with a warning message to logged on users after specified number of minutes - defaults to 15 minute delay Reboot.ps1 -DelayMinutes 20

Reboot.ps1

#requires -version 5.0
#Requires -RunAsAdministrator
<# DANGER REBOOTING!
   This is meant for a local machine in a scheduled task 
   and is not handling remoting or remote credentials
#>
[CmdletBinding()]
param (
    [Parameter()][int]$DelayMinutes = 15 #default to 15 minute delay if this parameter is not supplied
)
Begin {
    if (![System.Diagnostics.EventLog]::SourceExists("PowerShellRebootScript")){
        New-EventLog -Source 'PowerShellRebootScript' -LogName Application
    }
}

Process {
    $delaySeconds = $DelayMinutes * 60
    $restartTime = (Get-Date).AddMinutes($DelayMinutes)
    $msg = "This computer is being restarted. Save your work before $(Get-Date $restartTime -Format "yyyy-MM-dd HH:mm:ss zzzz")  or abort the restart by running   shutdown /a"
    
    shutdown /r /f /d P:4:1 /t`$($delaySeconds) /c "$msg" 2>$null
    msg * $msg
    
    if ($LastExitCode -ne 0) {
        Write-EventLog -Message "($env:username) failed to reboot ($env:computername) ($LastExitCode) script: $($myInvocation.myCommand.path)" -Source 'PowerShellRebootScript' -EventId 65110 -EntryType Warning -LogName Application
    }

    else {
        Write-EventLog -Message "($env:username) initiated reboot of ($env:computername) ($LastExitCode) script: $($myInvocation.myCommand.path)" -Source 'PowerShellRebootScript' -EventId 65109 -EntryType Information -LogName Application
    }

}
<#
References:
https://stackoverflow.com/questions/18107018/powershell-with-shutdown-command-error-handling/18109510#18109510
https://www.ciraltos.com/writing-event-log-powershell/
https://devblogs.microsoft.com/scripting/how-to-use-powershell-to-write-to-event-logs/
https://www.andreafortuna.org/2019/06/12/windows-security-event-logs-my-own-cheatsheet/
https://community.spiceworks.com/topic/2001422-create-scheduled-task-with-run-as-highest-level-whether-user-is-logged-or-not
https://ss64.com/ps/remove-eventlog.html
https://stackoverflow.com/questions/13851577/how-to-determine-if-an-eventlog-already-exists/26004087#26004087

$myServer01_svcCred = Get-Secret myServer01_svcCred

$taskName = "Reboot myServer01"
$description = "Restart myServer01 with a 15 min delay"
$principal = New-ScheduledTaskPrincipal -UserId $myServer01_svcCred.UserName -LogonType ServiceAccount -RunLevel Highest
$paswd = $myServer01_svcCred.GetNetworkCredential().Password

# Create a new task action
$taskAction = New-ScheduledTaskAction `
    -Execute 'powershell.exe' `
    -Argument '-File C:\PowerShellScripts\Reboot.ps1 -DelayMinutes 15'
$taskAction

#create a new task trigger weekly at 8pm
$taskTrigger = New-ScheduledTaskTrigger -Weekly -At 8PM -DaysOfWeek Friday
$taskTrigger

# Register the scheduled task
Register-ScheduledTask `
    -TaskName $taskName `
    -Action $taskAction `
    -Trigger $taskTrigger `
    -Description $description `
    -RunLevel Highest `
    -User $myServer01_svcCred.UserName `
    -Password $paswd
#>