Powershell: Change UPN on list of users

I needed a script to bulk change a list of users to a new UPN i came up with this.

#
$Users = gc c:\temp\users.txt | get-ADUser

foreach ($User in $Users)
$UserUPN = $User.UserPrincipalname
$UserUPNwithOutDomain = ([regex]::matches($UserUPN, "([^@]+)")).value[0]
Set-ADUser $User -userprincipalname "$UserUPNwithOutDomain@microsoft.com"
}

Powershell: Gather all user objects and report lastlogon and lastlogontimestamp to CSV file

Purpose:
Connects to active directory and pulls a list of all user objects and create a report of lastlogon and lastlogontimestamp values

Note: This is something i did around midnight so i need to do further testing on this script to ensure the data is correct and the lastlogon value will only be from the DC the script is running against

  
#Tony Unger
#Scans all user accounts and reports lastlogon and lastlogontimestamp attr.

Import-Module ActiveDirectory

$AllUsers = get-aduser -Filter * -SearchBase "DC=microsoft,DC=Com" -Property SamAccountName,Lastlogon,LastlogonTimeStamp | Select Name,UserPrincipalname,SamAccountName,@{Name='Last Logon Timestamp';Expression={[System.DateTime]::FromFileTime($_.LastLogonTimestamp).ToString('g')}},@{Name='Last Logon';Expression={[System.DateTime]::FromFileTime($_.LastLogon).ToString('g')}}

$AllUsers | Export-Csv -Path "c:\Audit_UsersLastLogon.csv" -NoTypeInformation