How to add or remove an email alias using Powershell

Open Power Shell as an Administrator

Go to Start
Search for Power Shell
Right click on Windows Power Shell
Run as Administrator

Run the following commands

Set-ExecutionPolicy RemoteSigned

(Need to configure this setting only once on your computer)
-Press “A” or “Y”
–Press Enter

 $UserCredential = Get-Credential

Windows Power Shell Credential Request
Enter Admin’s Username & Password

$Session = New-PSSession -ConfigurationName Microsoft.Exchange -ConnectionUri https://outlook.office365.com/powershell-liveid/ -Credential $UserCredential -Authentication Basic -AllowRedirection

Import-PSSession $Session -DisableNameChecking

Add an email alias to an Office 365 account

 Set-Mailbox "User's Name" -EmailAddresses @{Add='alias@yourdomain.com'}

Remove an email alias from an Office 365 account

Set-Mailbox "User's Name" -EmailAddresses @{Remove=’alias@yourdomain.com’}

If you are using MFA (multi-factor authentication) follow this link
Connect to Exchange Online Power Shell using multi-factor authentication

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