$Username = 'username'
$Password = 'password'
$pass = ConvertTo-SecureString -AsPlainText $Password -Force
$Cred = New-Object System.Management.Automation.PSCredential -ArgumentList $Username,$pass

$timeOnADFS = invoke-command -ComputerName ip.of.problem.server -ScriptBlock {get-date -UFormat %T} -Credential $Cred
$timeOnLocal = get-date -UFormat %T
echo "Time on ADFS server: $timeOnADFS"
echo "time on exchange server: $timeOnLocal"


$difference = (new-timespan -start $timeOnADFS -end $timeOnLocal).Minutes

$difference

if (($difference -gt 2) -or ($difference -lt -2)) {
       send-mailmessage -from "timeWarning@youremail.com" -to "thePeopleWhoWillFixIt@youremail.com" -subject "time difference is $difference" -body "time difference is $difference" -smtpserver "yourRelayServer.FQDN"
}