Change of Hosting to new provider

Hi,

I have recently changed provider for a clients domain and the hosting has also changed.

They currently use Windows Live with their email accounts and these are set up with the previous server settings (previous provider). I will need to update the settings so that they retain these email accounts without disruption. If I change the pop, smtp and password settings in the current email accounts, will this delete any information currently received, i.e emails, sent files, folders and contents and contacts etc.

I am not that sure of how Windows Live works, so am reluctant to make any changes as yet.

Any advice will be really appreciated.

Many thanks :)