To disable all enabled users from an Active Directory group use the following script. Replace the groupname with the correct groupname. Also this script will show what it does, but does not disable the accounts until you remove the “-whatif” option from the command: Disable-ADAccount -Identity $user -whatif

The original script comes from https://community.spiceworks.com/topic/380100-disable-enable-ad-account-based-on-group-membership

$Group = "groupname"
Try { Import-Module ActiveDirectory -ErrorAction Stop }
Catch { Write-Host "Unable to load Active Directory module, is RSAT installed?"; Exit }

Try {
    $GroupDN = (Get-ADGroup $Group -ErrorAction Stop).DistinguishedName
}
Catch {
    Write-Host "Unable to locate group: $Group because ""$($Error[0])""" -ForegroundColor Red
    Exit
}

ForEach ($User in (Get-ADUser -Filter * -Properties MemberOf))
{   If ($User.MemberOf -contains $GroupDN)
    {   
        If ($user.enabled)
        {
            Write-Host "Disabling $($User.Name)"
            Disable-ADAccount -Identity $user -whatif
        }
    }
} 

Use the following script to determine the uptime of your servers which are defined in a text file:

# Writer = Ritesh Parab; fb.com\parab.ritesh  
# File Name = Get-uptime 1.2
# Description = Get Server up time 
# function Date and time copied from Technet :)
# Error Handling : TRY and CATCH
# Bugs are welcome 2 [email protected]
# Fix > WMI Query time function added {from technet forum}


cls                                             
$erroractionpreference = "SilentlyContinue"
# Helper Function - convert WMI date to TimeDate object
function WMIDateStringToDate($Bootup) {
 [System.Management.ManagementDateTimeconverter]::ToDateTime($Bootup)
}

# Main script
$Computer = Get-Content "c:\Servers.txt"

foreach ($system in $Computer) {
$rtn = Test-Connection -ComputerName $system -Count 1 -BufferSize 16 -Quiet
	 	IF($rtn -match 'True') {
		$NameSpace = "Root\CIMV2"
		$wmi = [WMISearcher]""
	 	$wmi.options.timeout = '0:0:15' #set timeout to 10 seconds
	 	$query = 'Select * from Win32_OperatingSystem'
	 	$wmi.scope.path = "\\$system\$NameSpace"
	 	$wmi.query = $query
	  	Try{
	  	$wmiresult = $wmi.Get()
	  	#	$wmiresult
			foreach ($wmioutput in $wmiresult){
			   $Bootup = $wmioutput.LastBootUpTime
			   $LastBootUpTime = WMIDateStringToDate($Bootup)
			   $now = Get-Date
			   $Uptime = $now - $lastBootUpTime
			   $d = $Uptime.Days
			   $h = $Uptime.Hours
			   $m = $uptime.Minutes
			   $ms= $uptime.Milliseconds
			   $a = "$System Up for: {0} days, {1} hours, {2}.{3} minutes" -f $d,$h,$m,$ms
			   Write-Host "$a" -ForegroundColor Green
	  		   }
	  		}
		Catch {
	  			Write-host "WMI not available on : $System" -ForegroundColor Red
				Write-Output "WMI failed on $system because : $_" | Out-File "c:\failed.txt" -Force -Append 
	  	}
		}
		else{
			write-host "$system Offline" -ForegroundColor DarkRed
			Write-Output "$system Offline" | Out-File 'c:\failed.txt' -Force -Append 
		}
	} 

Source: http://www.rivnet.ro/2013/06/report-dhcp-scope-settings-using-powershell.html

A script to export information from all authorized DHCP servers in the Active directory. It will export the following information to a csv file:

DHCPServer name, Scope Name, Subnet defined, Start and End Ranges, Lease Times, Description, DNS Server, Gateway

import-module DHCPServer
#Get all Authorized DCs from AD configuration
$DHCPs = Get-DhcpServerInDC
$filename = "d:\backup\dhcp\DHCPScopes_DNS_$(get-date -Uformat "%Y%m%d-%H%M%S").csv"

$Report = @()
$k = $null
write-host -foregroundcolor Green "`n`n`n`n`n`n`n`n`n"
foreach ($dhcp in $DHCPs) {
    $k++
    Write-Progress -activity "Getting DHCP scopes:" -status "Percent Done: " `
    -PercentComplete (($k / $DHCPs.Count)  * 100) -CurrentOperation "Now processing $($dhcp.DNSName)"
    $scopes = $null
    $scopes = (Get-DhcpServerv4Scope -ComputerName $dhcp.DNSName -ErrorAction:SilentlyContinue)
    If ($scopes -ne $null) {
        #getting global DNS settings, in case scopes are configured to inherit these settings
        $GlobalDNSList = $null
        $GlobalDNSList = (Get-DhcpServerv4OptionValue -OptionId 6 -ComputerName $dhcp.DNSName -ErrorAction:SilentlyContinue).Value
        $scopes | % {
            $row = "" | select Hostname,ScopeID,SubnetMask,Name,State,StartRange,EndRange,LeaseDuration,Description,DNS1,DNS2,DNS3,GDNS1,GDNS2,GDNS3,Router
            $row.Hostname = $dhcp.DNSName
            $row.ScopeID = $_.ScopeID
            $row.SubnetMask = $_.SubnetMask
            $row.Name = $_.Name
            $row.State = $_.State
            $row.StartRange = $_.StartRange
            $row.EndRange = $_.EndRange
            $row.LeaseDuration = $_.LeaseDuration
            $row.Description = $_.Description
            $ScopeDNSList = $null
            $ScopeDNSList = (Get-DhcpServerv4OptionValue -OptionId 6 -ScopeID $_.ScopeId -ComputerName $dhcp.DNSName -ErrorAction:SilentlyContinue).Value
            #write-host "Q: Use global scopes?: A: $(($ScopeDNSList -eq $null) -and ($GlobalDNSList -ne $null))"
            If (($ScopeDNSList -eq $null) -and ($GlobalDNSList -ne $null)) {
                $row.GDNS1 = $GlobalDNSList[0]
                $row.GDNS2 = $GlobalDNSList[1]
                $row.GDNS3 = $GlobalDNSList[2]
                $row.DNS1 = $GlobalDNSList[0]
                $row.DNS2 = $GlobalDNSList[1]
                $row.DNS3 = $GlobalDNSList[2]
                }
            Else {
                $row.DNS1 = $ScopeDNSList[0]
                $row.DNS2 = $ScopeDNSList[1]
                $row.DNS3 = $ScopeDNSList[2]
                }
            $router = (Get-DhcpServerv4OptionValue -ComputerName $dhcp.DNSName -OptionId 3 -ScopeID $_.ScopeId).Value
            $row.Router = $router[0]
            $Report += $row            }
        }
    Else {
        write-host -foregroundcolor Yellow """$($dhcp.DNSName)"" is either running Windows 2003, or is somehow not responding to querries. Adding to report as blank"
        $row = "" | select Hostname,ScopeID,SubnetMask,Name,State,StartRange,EndRange,LeaseDuration,Description,DNS1,DNS2,DNS3,GDNS1,GDNS2,GDNS3,Router
        $row.Hostname = $dhcp.DNSName
        $Report += $row
        }
    write-host -foregroundcolor Green "Done Processing ""$($dhcp.DNSName)"""
    }

$Report  | Export-csv -NoTypeInformation -UseCulture $filename