There are a number of common country and language errors that may seem correct but are actually wrong and will give an error by the search engines.  


Using the Country Code "UK" for United Kingdom  


In the example below, the site was using "la" to designate this as their Latin America Site.  While fine in the sub directory, using it in the HREFLang element means something entirely different.  


<link rel="alternate" hreflang="en-UK" href="http://www.mysite.com.com/en-uk">

 

The HREFLang syntax is saying "en" representing the language of the site as "English" and "UK" which is the Country code for the "Ukraine" - the correct code for the United Kingdom is GB so this entry is incorrect.  


Using the Country Code "LA" for Latin America  


In the example below, the site was using "la" to designate this as their Latin America Site.  While fine in the sub directory, using it in the HREFLang element means something entirely different.  


<link rel="alternate" hreflang="es-LA" href="http://www.mysite.com.com/es_la">


The HREFLang syntax is saying "en" representing the language of the site as "Spanish" and "LA" representing the region of the language which is the Country code for "Laos" - there is NOT a code for Latin America so this is incorrect.  In this case, we suggest you set the /es-la site to Represent Multiple Countries of a region.  In this case, one of the countries in Latin America.  This takes care of the alternative URL issue and allows you to designate this site to multiple counties.   You can do this easily by replicating countries using our HREF Builder XML site map's functionality vs. bloating your pages by adding multiple entries in the page.