Editing photos in Photo Gallery

I save all of my photos to Dropbox and then edit them with Photo Gallery, but for some reason on my home office computer, when I click edit the window comes up with every photo I have ever taken basically and dropbox isn't even an option on the left hand side menu so that I can even search for my photos (even though I have double clicked on a specific photo and clicked edit while on that photo)... I have had THREE calls with tech support, paid $100, all for nothing, they can't fix it and told me to come here.  My computer has been refreshed, I have uninstalled and reinstalled Windows Essentials TWICE and nothing has helped.  Any ideas?  This is a crucial function of my job and I need to be able to use this.  I am on Windows 8. Thanks!