Google has now made it easy for you to monitor your country and language settings in Webmaster tools. If you log into your account and choose “International Settings” from the left navigation you will see the Language and Country screens. In this case 405 HREF Language Tags have been set for various pages on the site and Google has not found any problems with them.
In the following case, there are 58 errors. Looking at the errors they are showing that there are pages with HREF tags that do not have the local version included. In this case, there are 18 pages for Bulgaria that have HREF tags on them but the /bg page is not in the list of tags.
If you click into the error it will show you all the pages that have the problem.