Video files not there.

Hi
please anyone help. Just bought a nice lcd for the living room, and was
exited to finally get some use out of the mediacenter.
My video files are not visable in VMC.
No matter what drive or folder i place my .avi .mpg .vmw files on.
I can see the folder, but when mouse over it says "0 elements" , and when
opend folder it says " dosn´t contain video file". Tried several codec´s.
One more thing, media center is watching more folders than i allowed it to.
Eks. my drive H:\ allways shows. but it is not listed anywhere in
medialibary settings.
so i cant remove it.