I would check with your webhost. It may be in the sites cache or the folder structure has changed. In any case , I would contact my webhost.
I took your advice & called Earthlink, our web host. They wanted to check my FTP settings but just like when they changed their system a month ago, I could access the 'home page' for changing the FTP settings but I couldn't click on anything. When this happened a month ago, the web host rep
'took over' my computer & changed the FTP settings but after about 10 tries the web host rep I was speaking to this time failed to make the necessary connection so he could make the changes by taking over my computer. Then yelled at me saying I shouldn't rely on them, I should figure it out myself. When I asked to speak to a supervisor, he hung up on me. So I don't think I'll get anywhere by contacting them again.
Wow, Hung up on you? I think with the issues you are having, I think I would find a new webhost. There are a lot of them out there.