I've run into this with Pho.to! editor ever since I began using a few years ago. The photo looks like it saves as a blank but if you check its properties, you will see it saves as a 1 x 1 pixel image!
I've reported this bug before, several times.
Pho.to! editor does this randomly, I've never been able to find any kind of pattern in when it chooses to save a photo as a blank appearing page with the image properties being 1 x 1 pixel size.
It happens often enough that after the first few times I used the program and lost photos when I directed the program to just save and overwrite the original, that I never overwrite originals anymore because the risk of losing the original is so great.
Sometimes I can edit a bunch of photos and it won't do this blank page save. Other times, it does the blank instead of properly saving the image, every few photos.
It doesn't seem to be affected by size of photo being saved, lightness or darkness of photo being saved, amount of editing that's been done on the photo whether a lot or very little, number of photos you've edited in your session, it happens in both XP and Vista, on pcs with a lot of disk space and plenty of RAM and on pcs with very little disk space and skimpy RAM.
This bug in saving photos as just blank white pages with properties being 1 x 1 when you check properties in file details, happens totally randomly & its frustrated me for years.
I would LOVE to see this bug fixed too!