Importing pictures on Mac not working

I have had Photoshop Elements 10 for a long time and have imported many pictures but for some reason they won't import anymore.  Not sure what has been changed as I didn't change anything.  Also all previous imported photos from iPhoto now show not connected when previously they were.  When I try to reconnect them I get the message the photo was not connected and it also says the file already exists in the catalog but it does not.  HELP!