Upgrading from SQL2005 on one server to SQL2012 on another. I used KB918992 and was able to export from 2005 and import the sql authenticated user login accounts and passwords into 2012.
But not the Windows authenticated accounts.
Can you export and import the Windows authenticated accounts using a script to create logins, users , database roles and object level permissions of the specific database?
http://blog.sqlauthority.com/2008/03/01/sql-server-transfer-the-logins-and-the-passwords-between-instances-of-sql-server-2005/
http://support.microsoft.com/kb/918992
http://social.technet.microsoft.com/Forums/sqlserver/en-US/f1b82a0f-92c3-4748-85cb-c13105ad839d/move-the-users-and-logins-from-one-database-to-another-database-with-same-privileges