WIN 7 as media server - refresh of listed files

Hi Everybody

I do have a question that has more to do with WIN7 instead of the wdtv live but I got no hint yet.

I’m using WIN 7 as the media server.

I do have a files structure to sort my files.

after adding a file to the structure and navigating with my wdtv live via media server (not neworkshares) to it, the file is not presented. When navigation via network shares the file is presented and can be chosen.

Does somebody know how to influence the update rythm of the media database of the WIN 7 Media server?

Thanx in advance.