WMV Encoder missing, help

[awdrifter]

I just encoded some WMV videos using TMPGEnc last night, but when I try to encode some more today, the WMV codec is missing. What's wrong? What do I need to install to get that back? Thanks.

Here's a screenshot.
http://img465.imageshack.us/img465/6294/screenshotst5.jpg