PowerShell Script to get Office 365 last logons for Users and Guests.
Author : Cary GARVIN
Contact : cary(at)garvin.tech
LinkedIn : https://www.linkedin.com/in/cary-garvin
GitHub : https://github.com/carygarvin/
Script Name : Get-O365LastLogons.ps1
Version : 1.0
Release date : 05/05/2020 (CET)
History : The present script has been developed for Organizations to produce an audit view on Office365 last actions by users and guests in their Office365 tenant.
Purpose : The present Script generates a list of Office365 last logons along with basic information such as Workload (Office365 product), Client IP Address and so on.
The Script will output 2 CSV files, one with Last Logons for Office365 Users (differentiated on 'UserType' property) and another one for Office 365 Guests.
This script is to be launched within "Exchange Online PowerShell" in order to invoke the cmdlet Search-UnifiedAuditLog around which the present Script is built.
Running it from a PS-Session is not advised in case the User Management Admin account used to run it is subject to MFA.
Supply your O365 User Management Admin credentials to the MsolService when prompted.
Auditing for the O365 tenant should be enabled otherwise Unified Audit Logs could potentially not contain any worthwhile information...