In the released Windows 10 build 10041 there is a new login screen enabled by default. It features rounded avatars and a slightly different layout compared to Windows 8's login screen. Unfortunately, it is a bit buggy at this moment. If you do not wish to test the new login screen or if it is causing some unresolvable issues for you, here is how to disable the new login screen and restore the old login screen in Windows 10 build 10041.
Microsoft had rolled an updated build 10041 of Windows 10 and made it available via Windows Update. There is no ISO image available for download, so interested users need to refer to Windows Update as described HERE. Users who have already installed it face the issue that Mail, Calendar and People apps are not opening in this build. Here is an official fix courtesy of Microsoft.
Microsoft had rolled out an updated build 10041 of Windows 10 and made it available via Windows Update. There is no official ISO image available for download, so you cannot perform a clean install of the released build. However, if you expected to see many changes, it can be a bit of a downer.