[CPA]

Do you have photoshop elements or any other version of photoshop on your machine? Most cameras come either with a version of photoshop or another similar photo editing package.

I have the full version of photoshop. These directions should also work for "light" versions of photoshop, but I am not completely sure:

Start Photoshop
Click on File / Open and open the image you want to change.
Once your photo is onpened, click on Image / Image Size...
Make sure Constrain Proportions is checked.
First, change Resolution to 72 (this is a standard screen resoluton setting)
Then, in the dimensions box, make sure your units of measure are set to pixels and change the width to 100 (for landscape photos) or change height to 100 (for portrait) and click OK.
Click on File / Save for Web...
Make sure JPEG High is selected
Click Save
Type a descriptive file name (no blank spaces, just letters and numbers to be safe). Make sure the photo is being saved in the folder you want and click Save.

Then try uploading the photo you just saved.

Good Luck!