Looks fairly straightforward this - your host file was hijacked - once run then check out to see if the alarm stops by going to any AV site

Start OTS. Copy/Paste the information in the quotebox below into the panel where it says “Paste fix here” and then click the Run Fix button.

[Unregister Dlls]
[Win32 Services - Safe List]
YN -> (Norton Internet Security) Norton Internet Security [Auto | Stopped] -> 
[Registry - Safe List]
< HOSTS File > ([2008/01/20 21:24:21 | 000,007,369 | ---- | M] - 348 lines) -> C:\Windows\System32\drivers\etc\hosts
YN -> Reset Hosts -> 
[Custom Items]
:Files
ipconfig /flushdns /c
:end
[Empty Temp Folders]
[EmptyFlash]
[CreateRestorePoint]
  

The fix should only take a very short time. When the fix is completed a message box will popup telling you that it is finished. Click the Ok button and Notepad will open with a log of actions taken during the fix. Post that information back here

I will review the information when it comes back in.