Error -50


I've an "Error -50" each time i save for the second time a document with "Text Edit Plus", "Pepper" and "Graphic Converter", but not with the Text Edit given with OSX.

I've notice that this error occurs only if i save the document in my primary unix partition with OSX, on the secondary, that is in OS Extended format, all works fine.

I've no idea if this is a OSX error, a 3rd party software error or a problem with my OSX configuration.

Someone can suggest me a better idea than reinstall OSX formatting the primary partition in OS Extended format?