#Requires -Version 5.1
<#
    JbTecWiz Support Centre -- generated fix script

    Fault : A legitimate application is being blocked or quarantined
    Fix   : Check the detection before restoring anything
    Source: https://jbtecwiz.com/support/win-app-defender-block

    Run as     : Elevated PowerShell
    Expect     : 20 minutes
    Risk       : high
    Reversible : yes

    WHEN THIS IS THE RIGHT FIX
    A file has been quarantined. Find out what it was detected as first --
    the detection is right more often than not.

    HOW TO UNDO IT
    Remove-MpPreference -ExclusionPath removes the exclusion again.

    This script walks the fix one step at a time and asks before each
    one. Steps with no command are things you do yourself -- it prints
    those and waits. Run with -DryRun to print without executing.

    --------------------------------------------------------------------
    NO WARRANTY - USE AT YOUR OWN RISK

    This script is provided by JbTecWiz as-is and with no warranty of any
    kind, express or implied. You run it entirely at your own risk.

    JbTecWiz accepts no liability for any loss or damage arising from its
    use, including but not limited to data loss, downtime, or configuration
    changes that turn out to be wrong for your system.

    You are responsible for reading this script before running it, for
    satisfying yourself that it suits the machine in front of you, and for
    having a working backup first. Some steps cannot be undone.
    --------------------------------------------------------------------
#>

[CmdletBinding()]
param(
    # Print every step and command without running anything.
    [switch]$DryRun,
    # Do not ask before each step. Read the script first if you use this.
    [switch]$Unattended
)

$ErrorActionPreference = 'Stop'
$script:Failed = 0

function Write-Rule { param([string]$Text)
    Write-Host ''
    Write-Host ('-' * 70) -ForegroundColor DarkGray
    if ($Text) { Write-Host $Text -ForegroundColor Cyan }
}

function Show-Prose { param([string]$Text, [string]$Colour = "Gray")
    if (-not $Text) { return }
    $words = $Text -split "\s+"; $line = "  "
    foreach ($w in $words) {
        if (($line.Length + $w.Length) -gt 74) { Write-Host $line -ForegroundColor $Colour; $line = "  " }
        $line += "$w "
    }
    if ($line.Trim()) { Write-Host $line -ForegroundColor $Colour }
}

function Invoke-Step {
    param(
        [int]$Number, [string]$Do, [string]$Why,
        [scriptblock]$Command, [switch]$Manual, [string]$Shell = "powershell"
    )
    Write-Rule "  Step $Number of 5"
    Show-Prose $Do "White"
    if ($Why) { Write-Host ""; Show-Prose $Why "DarkGray" }

    if ($Manual) {
        Write-Host ''
        Write-Host '  -> Do this yourself, then press Enter to carry on.' -ForegroundColor Yellow
        if (-not $Unattended -and -not $DryRun) { [void](Read-Host) }
        return
    }

    Write-Host ''
    foreach ($l in ($Command.ToString().Trim() -split "`n")) {
        Write-Host ("    " + $l.Trim()) -ForegroundColor Green
    }
    Write-Host ''

    if ($DryRun) { Write-Host "  (dry run -- not executed)" -ForegroundColor DarkGray; return }
    if (-not $Unattended) {
        $a = Read-Host "  Run this step? [Y]es / [S]kip / [Q]uit"
        if ($a -match "^[Qq]") { Write-Host "  Stopped at your request."; exit 0 }
        if ($a -match "^[Ss]") { Write-Host "  Skipped." -ForegroundColor DarkGray; return }
    }
    try { & $Command }
    catch {
        $script:Failed++
        Write-Host ("  Step $Number failed: " + $_.Exception.Message) -ForegroundColor Red
        Show-Prose "The rest of the fix may depend on this. Read the write-up before carrying on." "Red"
        if (-not $Unattended) {
            $c = Read-Host "  Carry on anyway? [y/N]"
            if ($c -notmatch "^[Yy]") { exit 1 }
        }
    }
}

Write-Rule
Write-Host '  A legitimate application is being blocked or quarantined' -ForegroundColor White
Write-Host '  Check the detection before restoring anything' -ForegroundColor Cyan
Write-Host ''
Write-Host '  Risk: high   Reversible   20 minutes'
Write-Host ''
Show-Prose 'No warranty. Use at your own risk - JbTecWiz accepts no liability. Read it before you run it, and have a backup.' 'DarkYellow'
Write-Rule

if (-not $Unattended -and -not $DryRun) {
    $go = Read-Host '  Ready? [y/N]'
    if ($go -notmatch "^[Yy]") { Write-Host "  Nothing was changed."; exit 0 }
}

Invoke-Step -Number 1 -Do 'List the detections with their names.' -Command {
    Get-MpThreatDetection | Sort-Object InitialDetectionTime -Descending | Select-Object -First 10 ThreatID,InitialDetectionTime,Resources | Format-List
    Get-MpThreat | Format-Table ThreatName,SeverityID,Resources -Wrap
}

Invoke-Step -Number 2 -Do 'Look the threat name up. A detection of a genuine trojan family is a very different thing from a heuristic like Wacatac or a PUA classification of a system tool.' -Why '"It is a false positive" is the most common assumption and it is wrong about half the time. Two minutes reading the detection name tells you whether you are restoring a working file or reinfecting the machine.' -Manual

Invoke-Step -Number 3 -Do 'If you are confident it is legitimate, submit it to Microsoft for analysis and restore it.' -Command {
    Get-MpThreat | Format-List ThreatName,Resources
    & "$env:ProgramFiles\Windows Defender\MpCmdRun.exe" -Restore -Name 'Threat:Win32/Example'
}

Invoke-Step -Number 4 -Do 'Add a targeted exclusion -- the specific file path, not the whole drive.' -Command {
    Add-MpPreference -ExclusionPath 'C:\Program Files\LineOfBusiness\app.exe'
}

Invoke-Step -Number 5 -Do 'Review the exclusions periodically. An exclusion list nobody has looked at in three years is a standing hole.' -Command {
    Get-MpPreference | Select-Object -ExpandProperty ExclusionPath
}

Write-Rule "  Confirm it worked"
Show-Prose 'The application runs and the exclusion list contains only what you intended.' 'White'
Write-Host ''
if (-not $DryRun) {
    Get-MpPreference | Format-List ExclusionPath,ExclusionProcess,ExclusionExtension
}

Write-Rule
if ($script:Failed -gt 0) {
    Write-Host ("  Finished with " + $script:Failed + " failed step(s).") -ForegroundColor Yellow
    Show-Prose 'Read the full write-up at https://jbtecwiz.com/support/win-app-defender-block' 'Yellow'
} else {
    Write-Host '  Finished.' -ForegroundColor Green
}
Write-Host ''
Show-Prose 'To undo: Remove-MpPreference -ExclusionPath removes the exclusion again.' 'DarkGray'
Write-Rule