I burned a DOS boot CD. When I use it, I find that under DOS, opening some folders gives the prompt "Invalid directory". Why is that? Also, sometimes after opening a folder it shows as completely empty, but in fact there are files inside. One forum member said this might be related to whether the filenames are valid and to the file attributes. So how can I tell whether a filename is valid, and what the file attributes are? I'd appreciate some guidance from an expert.

