Preview of project Not Found

Hi All,

I’m creating a new project and already created some pages. All of a sudden I get a page with:

Not Found The requested resource /?4753 was not found on this server.

I also have this with "resource /index.html?4928 was not found on this server.

How can I fix this so that I can review my pages in Blocs again? Somebody knows?

Thnx

Jeroen