Verification failed due to host not found

Hi, I uploaded the html file and the link works, however the verification fails.

Verifcation failed due to host not found

The file is at http://themacsfarm.co.uk/zohoverify/verifyforzoho.html which is the link on the verification page, and this works fine. So why can't zoho find it?

I can't use the other methods.

Thanks