I use Windows Live Mail, and I have email hosting with Fasthosts.

I want to upgrade a 'Mail Lite' mailbox to a 'Mail Extra' mailbox... just to have a 2gb mailbox instead of the basic 100mb mailbox. 

I don't want to lose any previous emails or contacts I have already have in Windows Live Mail.

So, before I upgrade the mailbox type, I want to ensure that all existing emails are backed up. 

If I move all mail from Inbox and Sent Items to Windows Live Mail 'Storage Folders', are they then safely backed up? 

Or do I need to 'export' all old email that I want to retain for future reference and import again when the upgrade is completed?