We are currently going though a rebranding at work and I am looking for a Powershell script I can run to change everyone's exchange default email address to be the new one. I'd like to keep all existing email addresses users have, but add the new one and set it as default. We use Exchange 2010 and current email format is firstname.lastname@domain.co.uk it's the domain that is changing
I'm a relative newbie to Exchange but have a little Powershell knowledge so any assistance will be greatly appreciated.