# Import the Active Directory module for the Get-ADComputer CmdLet
Import-Module ActiveDirectory

# Get today's date for the report
$today = Get-Date

# Setup email parameters
$subject = "Active Server RDP Sessions - " + $today
$priority = "Normal"
$smtpServer = "mail.domain.com"
$emailFrom = "noreply@domain.com"
$emailTo = "youremail@domain.com"

# Create a fresh variable to collect the results. You can use this to output as desired
$SessionList = "ACTIVE SERVER SESSIONS REPORT - " + $today + "`n`n"

# Query Active Directory for computers running a Server operating system
$90days = $today.AddDays(-90)
$Servers = Get-ADComputer -SearchBase "OU=Server Accounts,DC=domain,DC=com" -Filter {Modified -gt $90days -and Enabled -eq $true} | sort Name


# Loop through the list to query each server for login sessions
ForEach ($Server in $Servers) {
    $ServerName = $Server.Name

    Write-Host Interrogating $ServerName

    # When running interactively, uncomment the Write-Host line below to show which server is being queried
    # Write-Host "Querying $ServerName"

    # Run the qwinsta.exe and parse the output
    $queryResults = (qwinsta /server:$ServerName | foreach { (($_.trim() -replace "\s+",","))} | ConvertFrom-Csv)

    # Pull the session information from each instance
    ForEach ($queryResult in $queryResults) {
        $RDPUser = $queryResult.USERNAME
        $sessionType = $queryResult.SESSIONNAME


        # We only want to display where a "person" is logged in. Otherwise unused sessions show up as USERNAME as a number
        If (($RDPUser -match "[a-z]") -and ($RDPUser -ne $NULL)) {
            # When running interactively, uncomment the Write-Host line below to show the output to screen
            #Write-Host $ServerName logged in by $RDPUser on $sessionType
            $SessionList = $SessionList + "`n`n" + $ServerName + " logged in by " + $RDPUser + " on " + $sessionType
        }

        # We also want disconnected sessions
        If ($queryResult.ID -like "Disc" -and $queryResult.SESSIONNAME -ne "services") {
            #Write-Host $ServerName logged in by $sessionType and disconnected
            $SessionList = $SessionList + "`n`n" + $ServerName + " logged in by " + $sessionType + " and disconnected "
        }
    }
}

# Send the report email
Send-MailMessage -To $emailTo -Subject $subject -Body $SessionList -SmtpServer $smtpServer -From $emailFrom -Priority $priority

# When running interactively, uncomment the Write-Host line below to see the full list on screen
$SessionList