you need a space after the final set of quote marks

<meta property="og:url" content="http://www.mywebaddress.com"/>

should be..likes this one

<meta property="og:url" content="http://www.mywebaddress.com" />

You need a space after the final set of quote marks

<meta property="og:url" content="http://www.mywebaddress.com"/> 

Should be..likes this one

<meta property="og:url" content="http://www.mywebaddress.com" /> 

you need a space after the final set of quote marks

<meta property="og:url" content="http://www.mywebaddress.com"/> should be

<meta property="og:url" content="http://www.mywebaddress.com" />

you need a space after the final set of quote marks

<meta property="og:url" content="http://www.mywebaddress.com"/>

should be..likes this one

<meta property="og:url" content="http://www.mywebaddress.com" />