Sansa clip audiobooks gone in my computer

On my sansa clip I have several audiobooks in the folder audiobooks.

But when I connect to computer I can’t see the content of the audiobook folder…

same problem with the podcast folder.

Music folder don’t have the problem.

 There is no problem with adding new audiobooks…

Old and new audiobooks can be seen on the sansa but in my computer only the new ones???

Can you see the folders if you change the Clip’s Settings/USB setting and then connect up?