New Guy – Error 404

I am new to this. The site was dumped on me by a friend in need so I am struggling to keep up. I have in the past year been able to add photo albums to the site. I tried again and now get the error. I have no idea where to go or what to do. The site is probably old – I think it is on version 2.something.

What can I do get past this. I know this is very vague and I would be happy to have someone step through the site yourself. There is nothing there proprietary that I would be concerned with – just need to get past this.

Thanks