On windows server 2012 R2, I create 5 accounts with password from administrator account. After that, I go to Control Panel\All Control Panel Items\Administrative Tools\Computer Management\Local Users and Groups\Group and then I create a group "RE". I add all 5 accounts to RE group.
After finished, I open sql server studio management and create window authentication account for group. The username is [ServerName]\RE.
Then I logout and use 1 of 5 accounts to login windows.
The problem is I cannot login sql server studio management by windows authentication mode.
So why? I create group account in sql server and all account added in that group.