As was communicated by Lufthansa for several weeks, their Miles & More website will be off-line while it is migrated to a new platform and retooled. Here is an excerpt directly from the Miles & More Website:
Moving into the Future
From 11 to 18 February 2012 the Miles & More system will be moved to a new, improved online platform.
The following services will not be available during the short move:
– Booking flight awards on all airlines
– Mileage upgrades
– Hotel and rental car awards
– Awards for non-travel-related partners such as buch.de
– Address changes
– Permission changes
– PIN changes
However, WorldShop and SWISS Shop awards can still be redeemed.
It is not possible to credit miles during this time. However, the miles you earn will not be lost, they will be credited to your account automatically after the system upgrade is completed.
Please note that all services which require a login will be unavailable from 7 am (CET) on 15 February until 7 am (CET) on 17 February.
Your Miles & More Team thanks you for your understanding and looks forward to providing you with an even better service in future.