NT server Security issue

There are serveral utilities that can help you out. Winternals makes a couple of ways of fixing this, like Locksmith. I personaly like to use the utility found at http://home.eunet.no/~pnordahl/ntpasswd/bootdisk.html

You have to make the floppy, but it works great and it is free. Download and follow the instructions. It gets more complicated with SCSI drivers and such.

If this computer is part of a Domain then you can use the NT User Manager program to connect to the machine and change the local accounts.

Now, if you are really desperate and the above disk won't work, you can try this. Although not recommended, it will get you back into the system. This will overwrite existing accounts. I guess this is a bad time to bring up if this is a domain controller. Be careful.

If you don't have the Emergency Repair Disks for this server then you could use one from another computer. It goes something like this.
1> Get to or install another computer with the same OS on it. Exactly the same as you are trying to recover.
2> Make an emergency repair disk on the second machine. The command is 'rdisk'.
3> Now boot the locked machine with the 3 NT startup disks.
4> When you get the option of what to restore, only restore the SAMfile. ANY other options will destroy your computer.
5> Reboot and login with the password from the second machine.

I wouldn't do this on a really important server. You may also loose any special accounts you made for services and such.

I had a simular problem once with NT 4.0 No one knew the admin password. This worked for me:

When Windows 2000/4.0 boots, it displays the logon prompt for a while and
then (if no keyboard or mouse activity occurs) starts the LOGON.SCR
screensaver. If you can access the system's files, you can replace
LOGON.SCR with CMD.EXE.

When the logon timeout occurs, Windows 2000/NT4.0 launches (in the context
of the system account) the command console rather than the screen saver.
Use NETUSER to change the administrator password or launch the
Computer Management console (COMPMGMT.MSC) to accomplish the task. If
you choose the former, issue the command NET USER ADMINISTRATOR
where is the new password you want to assign to
the administrator account.

How you replace the LOGON.SCR file with CMD.EXE depends on whether the
system uses FAT or NTFS. With FAT, you can boot from a Windows 9x or a
DOS boot disk. But for NTFS systems, you might need a solution such as
Winternals' NTFSDOS to access the file system or access the system
across the LAN. Regardless, once you have access to the
%systemroot%\System32 folder, rename LOGON.SCR to LOGON.BAK and then
copy CMD.EXE to LOGON.SCR.