After the launch of the Anniversary Update for Windows 10, Microsoft received a small number of reports of Windows 10 freezing when signing into Windows after installing the Anniversary Update. With the help of users and MVP’s who posted on this thread an investigation determined that a small fraction of users who had moved app information to a second logical drive could encounter this issue.
The Windows Update released on August 31st for Windows 10 includes a fix for this issue. This update is automatically applied when installing the Anniversary Update.
If you still have the Anniversary Update installed and are experiencing this issue, and are a user who has two logical drives and has moved their app data to a second drive, please follow the steps listed in the ‘Answer’ of this post to resolve your issue.
If you uninstalled Windows 10 or the Anniversary Update because of this issue, we recommend you re-install now using the Windows Update Assistant by going to the Windows 10 download page and clicking the Update Now button.