Re: W3C validator error - End tag for element "HEAD" which is not open

John Collins <>, 2010-11-07 13:15 -0800:

> I’m the webmaster of and after running my site 
> through the W3C markup validator.I got 7 errors. I understand most of the errors 
> and I’ll fix them however this one really bothers me:
> Line 7, Column 489: end tag for element "HEAD" which is not open

It seems like the cause of that problem is that your document is an XHTML1
document but you're trying to validate it as an HTML4 document.

So the real fix is to either:

  - manually validate your document as XHTML1 instead

  - or, change your HTML4 doctype to an XHTML1 doctype instead

As far as what the validator seems to *think* the problem is: It seems to
be saying that the problem is due to that fact that you are using XML/XHTML
self-closing tag syntax in a document that you are trying to validate as an
HTML4 document (instead of as an XHTML1 document).

If you want to validate your document as HTML4, I guess the only way to
"fix" that is to not use self-closing tag syntax.

But if you manually validate it as XHTML1, the only error the validator
will emit is:

  Line 15, Column 25: document type does not allow element "h1" here;
  missing one of "object", "applet", "map", "iframe", "button", "ins",
  "del" start-tag

...which is a real error in your document, regardless of what doctype you
try to validate it against. Because you have this:

  <span id="lblMain"><h1>Canadian Banks</h1></span>

...and h1 is not allowed as a child of span.


P.S. If you want to know the details about why the validator is emitting
the particular error report that it's emitting, look closely at the
explanation it gives for 'document type does not allow element "META" here'
error it's emitting for line 7:

  One common cause for this error is the use of XHTML syntax in HTML
  documents. Due to HTML's rules of implicitly closed elements, this error
  can create cascading effects. For instance, using XHTML's "self-closing"
  tags for "meta" and "link" in the "head" section of a HTML document may
  cause the parser to infer the end of the "head" section and the beginning
  of the "body" section (where "link" and "meta" are not allowed; hence the
  reported error).

So, it seems that because of a self-closing tag on some previous element,
the validator is inferring that that the head section has already ended
before it reaches the meta element for which it's emitting that message.

I think this could arguably be considered a bug in the validator. Or maybe
it's behavior that that's mandated by SGML or by something in the HTML4
spec. If so, it's arguably instead a bug in SGML or in the HTML4 spec.
Because as far as actual browser parsing behavior goes, there's nothing in
your source that would cause a browser to think that your head element is
not still open at the point where the validator emits that message.

Michael(tm) Smith

Received on Monday, 8 November 2010 08:51:49 UTC