OK, I’ve been getting a plethora of emails lately from google on this topic on perfectly functioning sites registered under my google analytics account.
Googlebot can’t access your site
Over the last 24 hours, Googlebot encountered 1 errors while attempting to retrieve DNS information for your site. The overall error rate for DNS queries for your site is 100.0%.
You can see more details about these errors in Webmaster Tools….
I think I figured out why!
I’d been using my original verification file (circa 2006) which was a complete html valid file:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> <head> <title>Untitled <meta http-equiv="Content-type" content="text/html; charset=iso-8859-1" /> </head> <body> googleFOOBARNUMBER.html </body> </html>
But, apparently sometime after 2008, Google changed that and over the years that style of site verification page finally has been deprecated and is now obsolete, hence the notifications, at least that’s my best guess.
A current verification file should just contain straight text with the google number in it, like below, and should be named the same (googleFOOBARNUMBER.html):
Hope this is helpful!
UPDATE: July 22, 2013
I’ve also gotten messages like this:
[Webmaster Tools] http://domainname.com/: Googlebot can’t access your site
I think these represent an error on Google’s part. They add a colon at the end of their link which makes it looking for a URL that doesn’t even exist.
From what I’ve read, you can ignore these messages.