You will need to remote access to the FactoryWiz server to perform this procedure.When setting up an SMTP user mailbox in Exchange Online (O365) it may be necessary to use powershell to turn off the default setting for SmtpClientAuthenticationDisabled
open powershell as admin and then load the Connect-ExchangeOnline module and then set that value for the mailbox Identity of the email user you are trying to use as an SMTP service account
NOTE: the italicized should be replaced with your company specific username values
Connect-ExchangeOnline -UserPrincipalName [Your Global Admin User Account]
Set-CASMailbox -Identity user@companyname.onmicrosoft.com -SmtpClientAuthenticationDisabled $false
Get-CASMailbox -Identity user@companyname.onmicrosoft.com | select SmtpClientAuthenticationDisabled