Fixing avatars

I notice a lot of avatars have disappeared with the transition to the new software, including mine. I'm still getting the hang of this new software and every time I try to upload an avatar from the control panel, I get an error message. The picture I was trying to upload was within the maximum allowable file size and pixel dimensions.
Is the Avatar that you are currently using the one that you were attempting to upload? If not,. let me know an I will look into it.