SharePoint Migration form SharePoint 2010 to SharePoint 2013.
SharePoint 2010 Site Templates have been migrated and deployed to the SharePoint 2013 environment. CompatibilityLevel is 15 (SharePoint 2013).
When accessing SharePoint, users would get an error message, saying that the page cannot be displayed.
On the SharePoint Server in the IIS logs, the error code 401 — Access denied would be logged. The username is not part of the log entry.