InDesign CC won't package my files

InDesign CC won't pacakge my graphic files with the following error; "Cannot copy necessary linked file(s).

I have recenly upgraded to CC version of InDesign, using InCopy text files, have never expreienced any issues with packaging before.

I also tried saving back to InDesign CS6 and opening in that version, also with the same error.

Any thoughts or assistance would be greatly appriiciated.

regards

Peter