Cannot copy some PDF files from pc to S3

[AC Question]

I have made PDFs of the past 15 years calendars and want to put a copy of them on myS3.

I am using a PC with W7 and some copy OK, but others will not copy. I have tried to move, copy & paste, cut & paste and nothing works for some of the calendars. All the files are between 41 and 66 Kb so I do not think it is a size problem, as I have nearly 7Gb free space on the card.

Any suggestions?

Thanks,

Lee