This article will explain how to upgrade from personal to business 123-mail. Upgrading your Personal mailbox to a Business level mailbox will give you additional features such as Shared Calendar and contacts, as well well as a huge 25GB storage quota.
Login to your 123-reg control panel.
Click on the Manage Email link.
Now click the More tab for the personal mailbox you wish to upgrade and click the Manage Type button.
Please Note: You will need to add a business package to your quota to be able to upgrade from a personal to a business mailbox.
Select the Business option and then click Upgrade.