[Plextalk] Updating the Firmware

Hi Everyone, I need some help. I have just got around to updating the firmware on my Plextalk Pocket, and I am having some problems. After trying several times, I finally got the file to download and save to my computer. I unzipped the files into a new folder as instructed and then copied that folder to my PTP. I can see, through my computer, that the files are there on my PTP, but, for some unknown reason, the PTP will not do the update. What am I doing wrong? Please help. Blessings, Naomi in Michigan