My company is about to switch over to a new web host. The new web host will also be our e-mail carrier. I'm going to login to my domain registar and change the name servers to point to the new web host.

I will then create the e-mail addresses for my employees. We're keeping the same domain name, so the email addresses will have the same @companyname.com suffix.

Some of my employees use Outlook as their email client. Before pointing the name servers over to the new web host, will they need to archive any e-mails that are currently sitting in their Outlook inbox if they don't want to lose them?

I was thinking that would not be necessary. I thought that when an email comes to the Outlook inbox, that email is a copy that's been pulled off of the web host's mail server. So, once that email is in the Outlook inbox, it is safe even when the connection to the current web host server is terminated.

Is that correct or do they still need to archive?