# Remove-SpecificTeamsVersions.ps1
# Removes specified vulnerable/old versions of classic Microsoft Teams and Teams Machine-Wide Installer.
# Leaves new Teams / MSTeams MSIX app installed.

$ErrorActionPreference = "Continue"

Write-Output "Starting targeted Microsoft Teams cleanup..."

# Versions to remove
$TargetVersions = @(
    "24334.1103.3302.5694",
    "25045.406.3471.2143",
    "24124.2402.2858.5617",
    "24004.1403.2634.2418",
    "23195.1506.2253.6778",
    "24277.3102.3183.2670",
    "24256.2502.3123.1",
    "24165.1306.2986.9504",
    "25031.702.3408.1909",
    "24244.507.3118.4732",
    "23119.303.2080.2726",
    "1.7.0.7956",
    "25044.2208.3471.2155",
    "24348.802.3311.5092",
    "23335.242.2641.4129"
)

# Stop Teams-related processes
$ProcessNames = @(
    "Teams",
    "ms-teams",
    "msteams",
    "Microsoft.Teams",
    "Update"
)

foreach ($ProcessName in $ProcessNames) {
    Get-Process -Name $ProcessName -ErrorAction SilentlyContinue |
        Stop-Process -Force -ErrorAction SilentlyContinue
}

Start-Sleep -Seconds 5

# Registry uninstall locations
$UninstallRegistryPaths = @(
    "HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\*",
    "HKLM:\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Uninstall\*"
)

# Remove matching Teams Machine-Wide Installer versions
Write-Output "Checking for targeted Teams Machine-Wide Installer versions..."

$MachineWideInstallers = foreach ($Path in $UninstallRegistryPaths) {
    Get-ItemProperty $Path -ErrorAction SilentlyContinue | Where-Object {
        $_.DisplayName -eq "Teams Machine-Wide Installer" -and
        $TargetVersions -contains $_.DisplayVersion
    }
}

foreach ($App in $MachineWideInstallers) {
    Write-Output "Found targeted Teams Machine-Wide Installer: $($App.DisplayVersion)"

    if ($App.UninstallString -match "\{[A-Fa-f0-9\-]{36}\}") {
        $ProductCode = $Matches[0]
        Write-Output "Removing Teams Machine-Wide Installer using MSI product code: $ProductCode"

        Start-Process -FilePath "msiexec.exe" `
            -ArgumentList "/x $ProductCode /qn /norestart" `
            -Wait
    }
    elseif ($App.UninstallString) {
        Write-Output "Removing Teams Machine-Wide Installer using uninstall string."

        Start-Process -FilePath "cmd.exe" `
            -ArgumentList "/c $($App.UninstallString) /quiet /norestart" `
            -Wait
    }
    else {
        Write-Output "No uninstall string found for Teams Machine-Wide Installer version $($App.DisplayVersion)."
    }
}

# Remove matching classic Teams per-user installs
Write-Output "Checking user profiles for targeted classic Teams versions..."

$UserProfiles = Get-ChildItem "C:\Users" -Directory -ErrorAction SilentlyContinue | Where-Object {
    $_.Name -notin @(
        "Public",
        "Default",
        "Default User",
        "All Users",
        "defaultuser0"
    )
}

foreach ($Profile in $UserProfiles) {
    $TeamsFolder = Join-Path $Profile.FullName "AppData\Local\Microsoft\Teams"
    $UpdateExe = Join-Path $TeamsFolder "Update.exe"
    $CurrentExe = Join-Path $TeamsFolder "current\Teams.exe"

    if (-not (Test-Path $TeamsFolder)) {
        continue
    }

    $DetectedVersion = $null

    if (Test-Path $CurrentExe) {
        $DetectedVersion = (Get-Item $CurrentExe).VersionInfo.FileVersion
    }

    if (-not $DetectedVersion -and (Test-Path $UpdateExe)) {
        $DetectedVersion = (Get-Item $UpdateExe).VersionInfo.FileVersion
    }

    if ($TargetVersions -contains $DetectedVersion) {
        Write-Output "Found targeted classic Teams version $DetectedVersion in profile: $($Profile.Name)"

        if (Test-Path $UpdateExe) {
            Write-Output "Attempting silent uninstall for profile: $($Profile.Name)"
            Start-Process -FilePath $UpdateExe `
                -ArgumentList "--uninstall -s" `
                -Wait `
                -ErrorAction SilentlyContinue

            Start-Sleep -Seconds 3
        }

        if (Test-Path $TeamsFolder) {
            Write-Output "Removing remaining classic Teams folder for profile: $($Profile.Name)"
            Remove-Item -Path $TeamsFolder -Recurse -Force -ErrorAction SilentlyContinue
        }
    }
    else {
        Write-Output "Skipping profile $($Profile.Name). Classic Teams version '$DetectedVersion' is not in target list."
    }
}

# Check HKCU-style per-user uninstall entries under user registry hives if loaded
Write-Output "Checking loaded user registry hives for targeted classic Teams uninstall entries..."

$LoadedUserUninstallPaths = Get-ChildItem "Registry::HKEY_USERS" -ErrorAction SilentlyContinue | ForEach-Object {
    "Registry::$($_.Name)\Software\Microsoft\Windows\CurrentVersion\Uninstall\*"
}

foreach ($Path in $LoadedUserUninstallPaths) {
    $UserTeamsApps = Get-ItemProperty $Path -ErrorAction SilentlyContinue | Where-Object {
        (
            $_.DisplayName -eq "Microsoft Teams" -or
            $_.DisplayName -eq "MicrosoftTeams"
        ) -and
        $TargetVersions -contains $_.DisplayVersion
    }

    foreach ($App in $UserTeamsApps) {
        Write-Output "Found targeted per-user Teams uninstall entry: $($App.DisplayName) $($App.DisplayVersion)"

        if ($App.UninstallString) {
            Start-Process -FilePath "cmd.exe" `
                -ArgumentList "/c $($App.UninstallString) --uninstall -s" `
                -Wait `
                -ErrorAction SilentlyContinue
        }
    }
}

# Verify new Teams remains installed
Write-Output "Checking for new Teams / MSTeams..."

$NewTeams = Get-AppxPackage -AllUsers -ErrorAction SilentlyContinue | Where-Object {
    $_.Name -eq "MSTeams"
}

if ($NewTeams) {
    Write-Output "New Teams / MSTeams is installed and was left in place:"
    $NewTeams | Select-Object Name, Version, PackageFullName | Format-List | Out-String | Write-Output
}
else {
    Write-Output "WARNING: New Teams / MSTeams was not detected."
}

# Final verification
Write-Output "Performing final verification..."

$RemainingMachineWide = foreach ($Path in $UninstallRegistryPaths) {
    Get-ItemProperty $Path -ErrorAction SilentlyContinue | Where-Object {
        $_.DisplayName -eq "Teams Machine-Wide Installer" -and
        $TargetVersions -contains $_.DisplayVersion
    }
}

$RemainingClassicTeamsFolders = foreach ($Profile in $UserProfiles) {
    $TeamsFolder = Join-Path $Profile.FullName "AppData\Local\Microsoft\Teams"
    $CurrentExe = Join-Path $TeamsFolder "current\Teams.exe"

    if (Test-Path $CurrentExe) {
        $Version = (Get-Item $CurrentExe).VersionInfo.FileVersion

        if ($TargetVersions -contains $Version) {
            [PSCustomObject]@{
                Profile = $Profile.Name
                Version = $Version
                Path    = $TeamsFolder
            }
        }
    }
}

if ($RemainingMachineWide -or $RemainingClassicTeamsFolders) {
    Write-Output "Targeted Teams cleanup completed, but some targeted versions may still remain."

    if ($RemainingMachineWide) {
        Write-Output "Remaining Teams Machine-Wide Installer entries:"
        $RemainingMachineWide |
            Select-Object DisplayName, DisplayVersion, UninstallString |
            Format-Table -AutoSize |
            Out-String |
            Write-Output
    }

    if ($RemainingClassicTeamsFolders) {
        Write-Output "Remaining classic Teams folders:"
        $RemainingClassicTeamsFolders |
            Format-Table -AutoSize |
            Out-String |
            Write-Output
    }

    exit 1
}
else {
    Write-Output "Targeted Teams versions were successfully removed or were not present."
    exit 0
}