Renew MSO 365 Groups, for MS Teams

<#
Script:         Auto-Renew Groups; Thwart Expirations
Date:           June 2020
Scripter:       Trey Bentley
Description:    This script renews MSO 365 groups, so that they don't expire.
    Requires the Group's ID, to avoid same-name conflicts. Run as a weekly
    scheduled task in Task Scheduler with something like:
        Action: Start a program
        Program/script: C\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
        Add an argument: -File "C:\Scripts\MS_Teams\expirationExceptions.ps1"
#>

#############################
#   User Variables
#############################
# List the IDs of the group(s)/team(s) to auto-renew.
$renewGrps = @(
"b945caa3-2d6b-420c-9589-ca3b2df54ff4", # Exception Team 1
"8f610d8d-1105-4218-ab18-94565efba92e", # Exception Team 2
"9910e40a-91ba-49a9-9b41-04b5b64e2520"  # Exception Team 3
);  ##### !!!!!!! No comma on the last entry. !!!!!!! #####

###############
#   AzureAD Online Credentials
###############
# What is the Global Admin Service Account for your AzureAD?
$aadUsr = "ga@initech.net"

# Where is the secure password file for the above service account?
# You can create the file with something like:
#PS>    (Get-Credential).Password | ConvertFrom-SecureString | Out-File "ad_LdapUser.pwd"
$aadPwdFile = "./secure.pwd";

###############
#   Log File
###############
# Where do you want for your log file to go?
#   Provided is same path as scriptfile, and with the same name as the
#   scriptfile, but with a .log extention.
# $logFile = "./" + (split-path $MyInvocation.PSCommandPath -Leaf).split('.')[0] + ".log"
$logFile = "./" + (split-path $MyInvocation.PSCommandPath -Leaf).split('.')[0] + ".log"

#############################
#   Initialize
#############################

# Set up credential variable for use in a few nanoseconds.
$aadPwd  = Get-Content "${aadPwdFile}" | ConvertTo-SecureString;
$cred = New-Object -TypeName System.Management.Automation.PSCredential -ArgumentList $aadUsr,$aadPwd;

# Import the module, and connect to AzueAD.
Import-Module AzureAD;
Connect-AzureAD -Credential $cred;

# Create the sesion, and import it for use.
$aadSession = New-PSSession -ConfigurationName Microsoft.Exchange -ConnectionUri https://ps.outlook.com/PowerShell/ -Credential $cred -Authentication Basic -AllowRedirection;
Import-PSSession $aadSession;

# Logger Feature
function log{
    param($msg)

    $time = (Get-Date -f "yyyy-MM-dd HH:mm:ss")
    Write-Host "${time} ${msg}"
}

Start-Transcript -Path "${logFile}" -Append -IncludeInvocationHeader
log "######################################################";
log "Starting new run.";

#############################
#   Main Script
#############################
foreach ($grp in $renewGrps) {
    log "Attempting to renew: ${grp}";

    $timeOld = (Get-AzureADMSGroup -Id $grp).RenewedDateTime;
    log "Current renew timestamp: ${timeOld}";

    log "Attempting to reset timestamp";
    $renewRs = Reset-AzureADMSLifeCycleGroup -GroupId $grp;
    log "Result: ${renewRs}";

    $timeNew = (Get-AzureADMSGroup -Id $grp).RenewedDateTime;
    log "Current renew timestamp: ${timeNew}";
}


log "Removing session....";
Remove-PSSession $aadSession

log "Stopping transcript....";
Stop-Transcript;