My Web Galleries won't open

I have been making Web Galleries using Adobe Bridge within CS6.  Now, after making one, when I click on the "index" file, the browser window opens but the gallery will not load.  I am doing everything as I always have.  Tried Firefox, Edge and Explorer . . . all same result.  But old galleries created months ago that used to work now do not . . . same result with them. 

Any ideas appreciated.   Ross