What's a file extension? Look at the file name... "randompicture.thispartrighthereisthefileextension."
Commonly supported file extensions are ".gif" and ".jpeg" How do you save something as a jpeg?
Open Photoshop and go to "Save A Copy." After typing in the name, there should be a box listing numerous options. Click the one you want and hit okay.
If you've saved them as jpegs or gifs and they still won't upload, there's a good chance your file size is too big. Open Photoshop and hit "Image Size." Reduce your pixels and make sure that the "constrain proportions" box is checked. Hit okay and go through "save as copy" again if you want to leave the original picture the original size. If not, you can just hit save. [ MW8305's advice column | Ask MW8305 A Question ]
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