Media Center 2006 Burning DVD-R

I know this has been asked a hundred times, a hundred different ways, but I
have to inquire for myself...

I have Windows Vista with Windows Media Center 2006. I can record programs
just fine, but I cannot burn them. It complains, "Please insert writeable
media that is compatible with your DVD...." I insert a DVD-R, and it
complains again (same message). I tried inserting a new DVD to see if it
wanted to format it itself; no. I formatted it from Explorer, then inserted
it; no.

I finally located the stored file and used Explorer to copy it to the DVD-R.
It worked.

Why will it not work directly through Windows Media Center though? I've
read about all these encoders, Sonic, Nero, etc. I'm not interested in
buying anything else. This system came with everything, all who fleet of
Roxio software, etc.

If Explorer can do it, why can't Media Center? Any simple answers?

Thanks!

maybe copywriter protection