If you want, you can save a backup of your contact list of MSN Messenger or Windows Live Messenger.
You just need to open your MSN, sign in to your account, go to the Contacts menu and select the option Save contact list. After some seconds, the program will generate a file with the CTT extension (*.ctt) with your contact list in XML format.
With your contact list saved, you will be able to move your contacts to other MSN account, share your contacts with your friends or save your list as a backup in case of lost your account.
To import your contacts from the CTT file, you just need to go to the Contacts menu, and to select the option Import contact list selecting the CTT file with your contacts.