Why do I get error that filenames longer than 31 characters are unsupported?

I have read more than one post on this happening on Mavericks, yet I see nothing that indicates anything other than yep, it is an intermittent problem. To summarize:

When saving a file, or exporting to PDF, or printing to PDF, etc., the filesystem will sometimes throw an exception:

1. Error dialog presents: "Names longer than 31 characters are not supporred on the destination volumne."

2. If the filename is shortened, it is "accepted" yet no file is saved at the destination folder.

3. (In my observation) The previously used destination folder is not remembered for saving/exporting subsequent files. (This seems consistent with the files not actually being saved, despite shorter filenames.

This is very problematic, and it has occurred numerous times. Disk Utility shows no problems with the hard disk (using Verify). Rebooting seems to clear it up (sometimes), but it is pretty silly for a Mac to require a reboot like that (that sounds like Windows).

Any help / response would be appreciated.