Problem with files on thumb drives

After I upgraded to Mavericks, 2 USB thumb drives render some .doc (pages) text files "invisible" = unusable as back ups. smart status is not supported on either of them. No such problems with PDF files.
Anything I can do?
MacBook Pro 5.1 late 2008.
V.X10.95. Thank you.

S.M.A.R.T. status is not supported on external or attachable drives so that is not your problem. What kind of files are rendered invisible? Text or Pages? Files that are invisible have a period before them (.vol).

,doc are Microsfot Office format. Got Office on your MBP?

Thank U. Here is 1 of the invisible files Petey,1997#21.doc
I wrote id in Pages: Petey,1997#21.pages, used Pages to convert it to Word giving me the .doc format.
If I try to add the invisible file:error message: an older item by same name already exists.
Options:stop,keep both, replace. If I "replace" error message says: operation can't be done" but the file shows up, but temporarily only :-((((

That's an illegal file name (illegal characters within) which may be why it's showing up as hidden. Rename the file by removing the comma and the # and try again.

Go back to pages, open the file and convert it back to .Doc using a filename without the comma and hash sign like chscag said.

Cheers ... McBie

Thank you! will definitely try. Weird thing though... other files named exactly the same way but different year show up. Will let U know.