You have not provided much information e.g. when the error occurs, which version of Photoshop do you have, which OS are you using (Mac vs PC) etc.
Without more information, here is a link with similar error messages. Hope this helps
Anyway: here`s what I got:
Sometimes Photoshop doesn`t want to open certain file types for no reason, just because of the way they were saved. If that happens, you can open the file in Paint or other similar program, and just save it again as JPEG or PNG.
It could also be that Photoshop doesn`t have the permission to access the file. In that case, try opening it as an administrator (right-click -> open as administrator)