The problem is a login requires placement of a cookie in your browser’s cache. If you open IE and open the page that contains the login box (i.e. the Blog), you will see an icon of an eye on the lower toolbar of the browser window. This is a privacy report notification. Click on this icon to launch the cookies settings. Click on the web address of the server that contains the login page (i.e. the server hosting your Blog) and set to ‘always allow cookies on this site’. Now return to the page containing the login to your Blog in an iFrame, you should be able to login.
