I use picasa all the time and just moved from my pc to my mac using an external hard drive. I then restored all my photos to the mac. All seemed fine at first but now picasa seems to have a file date which is different from the camera or digitized date (in some cases twenty years apart). It seems to have redated all my photos randomly. They therefore no longer sort in date order - its all very odd and I can't find any posts about this. I have removed and replace the folder as a watched folder and refreshed all thumbnails but can't seem to fix it without drastic action. Any suggestions?

Thanks

I use Picasa to manage my photos. I recently switched from a Windows machine to a Mac, so I used an external hard drive to transfer my photos from the old computer to the new. Everything was fine at first, but now Picasa seems to have a file date which is different from that in the photo metadata (in some cases twenty years apart). It seems to have redated all my photos randomly. They therefore no longer sort in date order. 

I have removed and replaced the folder as a watched folder and refreshed all thumbnails but this didn't give me the desired behavior. What can I do to restore the correct dates on my photos?