Four days ago I was running V 2.3 and my blog suddenly went offline - all I could see was the Index/blog page with text listing of the directory and could not log in using admin access. - all attempts were directed back to this page.
So I reinstalled V2.7 as I did not want to go tot he latest version and got it working again. Changed my passwords and thought it was sweet. 24 hours later it had reverted to the original problem again.
Then I upgraded again to latest version - changed passwords again and it happened again.
I have no idea what is happening or how I can diagnose what the problem is - if the site has been hijacked or what to do - can anyone help?