Explorer.exe does not see cd/dvd files on cold reboot

After a cold reboot (using vista home premium), explorer does not see my
cd/dvd files. It brings up "burn a disc" dialogue and asks whether I
want to format the disc. Other software like Windows Media Player reads
the content. Restarting explorer.exe using Process Explorer fixes the
problem. Is there a registry fix, or an explorer repair I can do?