# ============================================================================ 
# Script: Get-InactiveUsers-ComprehensiveReport.ps1 
# Description: Categorizes users by inactivity period and generates detailed reports 
# Requirements: Microsoft.Graph PowerShell module, Entra ID Premium P1/P2 license 
# ============================================================================ 
 
# Connect to Microsoft Graph with required permissions 
Write-Host "Connecting to Microsoft Graph..." -ForegroundColor Cyan 
Connect-MgGraph -Scopes "User.Read.All", "AuditLog.Read.All" 
 
Write-Host "Retrieving all users from Microsoft Entra ID..." -ForegroundColor Cyan 
# Get all users with required properties 
$users = Get-MgUser -All -Property DisplayName,UserPrincipalName,AccountEnabled,CreatedDateTime,SignInActivity 
 
Write-Host "Processing $($users.Count) users..." -ForegroundColor Cyan 
 
# Process and categorize users 
$report = $users | ForEach-Object { 
    $lastInteractive = $_.SignInActivity.LastSignInDateTime 
    $lastNonInteractive = $_.SignInActivity.LastNonInteractiveSignInDateTime 
 
    # Determine most recent sign-in 
    $mostRecentSignIn = @($lastInteractive, $lastNonInteractive) |  
       Where-Object {$_ -ne $null} |  
       Measure-Object -Maximum |  
       Select-Object -ExpandProperty Maximum 
 
    # Calculate days inactive (from last sign-in to current date) 
    if ($mostRecentSignIn) { 
        $daysInactive = [math]::Round((New-TimeSpan -Start $mostRecentSignIn -End (Get-Date)).TotalDays) 
    } else { 
        $daysInactive = $null 
    } 
 
    # Categorize based on inactivity period 
    $category = switch ($daysInactive) { 
        {$_ -eq $null} { "Never Signed In" } 
        {$_ -le 30} { "Active (0-30 days)" } 
        {$_ -le 60} { "Moderately Inactive (31-60 days)" } 
        {$_ -le 90} { "Inactive (61-90 days)" } 
        default { "Highly Inactive (90+ days)" } 
    } 
 
    # Create custom object for reporting 
    [PSCustomObject]@{ 
        DisplayName = $_.DisplayName 
        UserPrincipalName = $_.UserPrincipalName 
        AccountEnabled = $_.AccountEnabled 
        CreatedDateTime = $_.CreatedDateTime 
        LastInteractiveSignIn = $lastInteractive 
        LastNonInteractiveSignIn = $lastNonInteractive 
        MostRecentSignIn = $mostRecentSignIn 
        DaysInactive = $daysInactive 
        InactivityCategory = $category 
    } 
} 
 
Write-Host "`nExporting reports..." -ForegroundColor Cyan 
 
# Export full report 
$fullReportPath = "UserActivity_FullReport_$(Get-Date -Format 'yyyyMMdd_HHmmss').csv" 
$report | Export-Csv -Path $fullReportPath -NoTypeInformation 
Write-Host "Full report exported to: $fullReportPath" -ForegroundColor Green 
 
# Generate summary statistics 
$summary = $report | Group-Object InactivityCategory |  
   Select-Object Name, Count |  
   Sort-Object Count -Descending 
 
Write-Host "`n========================================" -ForegroundColor Yellow 
Write-Host "User Activity Summary" -ForegroundColor Yellow 
Write-Host "========================================" -ForegroundColor Yellow 
$summary | Format-Table -AutoSize 
 
# Export highly inactive users separately 
$highlyInactive = $report | Where-Object { 
    $_.InactivityCategory -eq "Highly Inactive (90+ days)" -or  
   $_.InactivityCategory -eq "Never Signed In" 
} 
 
$highRiskReportPath = "HighRisk_InactiveUsers_$(Get-Date -Format 'yyyyMMdd_HHmmss').csv" 
$highlyInactive | Export-Csv -Path $highRiskReportPath -NoTypeInformation 
Write-Host "`nHigh-risk inactive users exported to: $highRiskReportPath" -ForegroundColor Green 
 
Write-Host "`n========================================" -ForegroundColor Yellow 
Write-Host "Summary" -ForegroundColor Yellow 
Write-Host "========================================" -ForegroundColor Yellow 
Write-Host "Total Users Processed: $($users.Count)" -ForegroundColor White 
Write-Host "High-Risk Inactive Users: $($highlyInactive.Count)" -ForegroundColor Red 
Write-Host "`nReports Generated:" -ForegroundColor White 
Write-Host "  1. $fullReportPath (all users)" -ForegroundColor White 
Write-Host "  2. $highRiskReportPath (90+ days or never signed in)" -ForegroundColor White 
Write-Host "`nScript completed successfully!" -ForegroundColor Green 
Write-Host "========================================" -ForegroundColor Yellow 
 
# Disconnect from Microsoft Graph 
Disconnect-MgGraph | Out-Null 
Write-Host "`nDisconnected from Microsoft Graph." -ForegroundColor Cyan