Assuming you can access the local machine with local
administrator rights, it is relatively straightforward to reset the system
administrator (sa) password on a MS SQL Server installation. This can be a
lifesaver if you have no other way to connect to the server, but it can also be
used by black hats to hack into your server. The key to avoiding this is to
ensure the server itself is secure and to keep enemies from gaining access to
an account with local admin privileges.