This article will explain how to change your VPS operating system.
Login to your 123-reg control panel
Click on the Manage link under the VPS section.
Click on the Manage button next to your VPS.
Click on the Manage VPS tab.
Click on the Change OS link next to Operating system under the Server Information section.
Select the operating system you wish to change to from the drop down list
When a operating system is selected click on the Reimage VPS button to complete.
Please note: All data will be lost when the server is reimaged.