>Hello All, thanks for your detailed response, I don't know what kicked all this off but its sure made a good job of it, I reinstalled IIS so http is up and running but I'm still getting the same behaviour, I always use Firefox and have never seen this Yahoo page before, running my local sites has never been a problem and if I get an error I used to get the normal ASP page with the stack trace etc..., how do I know if my browser is hosted by Yahoo ? What's really puzzling me is what on earth has changed, I didn't change any code, haven't updated ( to my knowledge ) Firefox, no new Windows updates etc etc... Weird

For a while Yahoo was offering "Firefox optimized for Yahoo" on their home page. I see it's still available: https://downloads.yahoo.com/firefox/ . If that's where you got FireFox that might explain things.

Do you have any toolbars, extensions or other add-ons installed in FireFox?

You could also try uninstalling, then reinstalling FireFox (optionally back up your profile first).

If all that fails it wouldn't hurt to do an in-depth antivirus/antimalware scan. These days most such hook into your networking stack and do funky things.