How to change the cache directory for downloads of thumbnails and art

Hi,

I am running Windows 7 with Media Center on a HTPC, and all the media/content is stored on a NAS. Because this PC is used by kids and guests, it has a READ-ONLY access to my NAS and its content.

However, I noticed that each time I access the music folder, windows starts (again!) to build the album art library for each song I have (my NAS has A LOT of content). Same goes for all our pictures.. When we first access the pictures (after a reboot?) Media Center has to REBUILD the thumbnail for EACH PICTURE. This takes a lot of time.

I could be wrong, but I think that the problem is that the PC tries to write the thumbnails and album art in each directory on the NAS, and obviously is denied writing rights.

What I would like to do is have Media Center cache those thumbnails and album arts LOCALLY, so that it doesn't have to rebuild them each time.

Would anybody know if there is a way for specify an ALTERNATE (local) directory for those album art, video and picture thumnails, etc?

Thanks