Report of all classic SharePoint sites

Install-Module PnP.PowerShell -Scope CurrentUser

# Connect to SharePoint Admin
Connect-PnPOnline -Url "https://<your-tenant>-admin.sharepoint.com" -Interactive

# Get all site collections
$sites = Get-PnPTenantSite

# Filter classic team sites (STS#0) and communication sites (optional)
$classicSites = $sites | Where-Object { $_.Template -eq "STS#0" -or $_.Template -eq "STS#1" }

# Result array
$results = @()

foreach ($site in $classicSites) {
    Write-Host "Processing site: $($site.Url)" -ForegroundColor Cyan
    Connect-PnPOnline -Url $site.Url -Interactive

    # Get root site details
    $web = Get-PnPWeb -Includes Title, Url, WebTemplate, LastItemModifiedDate
    $groups = Get-PnPGroup

    $owners = ($groups | Where-Object { $_.Title -like "*Owners*" }).Title -join "; "
    $members = ($groups | Where-Object { $_.Title -like "*Members*" }).Title -join "; "

    $results += [PSCustomObject]@{
        SiteTitle        = $web.Title
        Url              = $web.Url
        Template         = $web.WebTemplate
        LastModified     = $web.LastItemModifiedDate
        Owners           = $owners
        Members          = $members
        StorageUsageMB   = $site.StorageUsageCurrent
    }

    # Recursively get all subsites
    $subsites = Get-PnPSubWeb -Recurse
    foreach ($sub in $subsites) {
        $subGroups = Get-PnPGroup -Web $sub
        $subOwners = ($subGroups | Where-Object { $_.Title -like "*Owners*" }).Title -join "; "
        $subMembers = ($subGroups | Where-Object { $_.Title -like "*Members*" }).Title -join "; "

        $results += [PSCustomObject]@{
            SiteTitle        = $sub.Title
            Url              = $sub.Url
            Template         = $sub.WebTemplate
            LastModified     = $sub.LastItemModifiedDate
            Owners           = $subOwners
            Members          = $subMembers
            StorageUsageMB   = ""
        }
    }
}

# Export to CSV
$results | Export-Csv -Path "ClassicSitesReport.csv" -NoTypeInformation -Encoding UTF8
Write-Host "Report generated: ClassicSitesReport.csv" -ForegroundColor Green

 Replace:
<your-tenant> with your tenant name in the admin URL (e.g., contoso → https://contoso-admin.sharepoint.com).

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