When Microsoft develops a new version of a product, new exams are introduced and exams for previous versions are eventually retired. If you do not pass within the specified time frame, you will be decertified. You can be re-certified at any time by taking the specified alternate exam. You do not need to retake any non-retired exams which you previously passed. As a professional certified by Microsoft, you will benefit from being a member of an elite class of computer experts.
Employers respect the initiative and drive it takes to get certified.
A certification is proof of your IT knowledge and skills. Other certification benefits include use of the Microsoft certification logo and title, free subscriptions to selected Microsoft publications and access to special Microsoft web sites and Beta versions of software.