For better SEO I need put some meta on my page like this:
<!-- Schema.org markup for Google+ -->
<meta itemprop="name" content="The Name or Title Here">
<meta itemprop="description" content="This is the page description">
<meta itemprop="image" content="http://www.example.com/image.jpg">
Then I check this code on Markup Validation Service:
<!DOCTYPE html>
<html>
<head lang="en">
<meta itemprop="name" content="The Name or Title Here">
<meta itemprop="description" content="This is the page description">
<meta itemprop="image" content="http://www.example.com/image.jpg">
<meta charset="UTF-8">
<title>My title</title>
</head>
<body>
My body.
</body>
</html>
Throwing this error:
Line 4, Column 57: The
itempropattribute was specified, but the element is not a property of any item.<meta itemprop="name" content="The Name or Title Here">Line 5, Column 70: The
itempropattribute was specified, but the element is not a property of any item.<meta itemprop="description" content="This is the page description">Line 6, Column 68: The
itempropattribute was specified, but the element is not a property of any item.<meta itemprop="image" content="http://www.example.com/image.jpg">
How can I fix this?
You should explicitly provide a type these properties (name, description, image) belong to.
In Schema.org, everything is a Thing. Thing has many child types, listed under "More specific Types". Start there and choose the most specific type for your content.
For example: WebPage, Article or maybe BlogPosting.
It could look like (using WebPage as example here):
<html itemscope itemtype="http://schema.org/WebPage">
If you use itemprop meta tag in header for your site title, description and so on.
only just add itemscope itemtype="http://schema.org/WebPage" in your html tag.
finally:
<html itemscope itemtype="http://schema.org/WebPage">
来源：https://stackoverflow.com/questions/29123445/validation-error-the-itemprop-attribute-was-specified-but-the-element-is-not