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I installed firefox web developer tools when i try to validate page then i got an error. the screen shot of error below

enter image description here

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possible duplicate of What is port forwarding and what is it used for? – Nifle Apr 13 '12 at 18:43
@Nifle how is this a duplicate? – KronoS Jul 13 '12 at 3:32
@KronoS - It's been a while. But I suspect my reasoning was that the linked question explains the basics about localhost, routers and how to access local pages from the web. – Nifle Jul 13 '12 at 7:40
up vote 3 down vote accepted

The RFC 3330 explains you why: - This block is assigned for use as the Internet host loopback address. A datagram sent by a higher level protocol to an address anywhere within this block should loop back inside the host. This is ordinarily implemented using only for loopback, but no addresses within this block should ever appear on any network anywhere [RFC1700, page 5].

The important part here is loop back inside the host which basically means that you are visiting the site on your own computer, hence it is not public. What you do when doing the validation is sending your localhost IP to them and they can't really resolve that as it's local to you. Hence, if you want to validate it with the click of a button you would have to host your site first...

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