Forgot Password

See the following www.sysinternals.com
Locksmith v1.0 Locksmith is an add-on program to NTRecover that allows for the changing of passwords on systems where the administrative password has been lost. It works 100% of the time, and if you've forgotten the password to your machine, you can gain entry within minutes using Locksmith.

If changing the password is not a option you can get LC4 from @stake(http://www.atstake.com). It's a password cracking system, that can sniff the network for passwords, grab the passwords from a NT4 box including domain controllers) It will also get them from a local machine. They have a trial version available on their web-site that will do the job but you don't get the Brute Force attack.

Resetting Administrator?s password in Windows NT 4.0 can be done without using a third party software (either commercial or freeware).

The procedure has been available thru various articles including the TechRepublic forum.

If the file system is FAT16, all you need is a Windows 98 Startup disk.

1. Boot the computer with a Win98 Startup disk.
2. Navigate to C:\Winnt\System32
3. Rename file logon.scr to logon.old (Ren logon.scr logon.old)
4. Copy file cmd.exe to logon.scr. (Copy cmd.exe logon.scr)
5. Take out the 98 Startup disk.
6. Reboot the computer.
7. Wait 15 minutes and do not move mouse or KB in the mean time.
8. Instead of default Logon screen saver, Command prompt Windows will appear.
9. Type ?MUSRMGR? without the quotes to start User Manager.
10. Change the Administrator?s password. Exit User Manager.
11. Copy logon.old back to logon.scr (Copy logon.old logon.scr)
12. Type ?Exit? without the quotes to exit the Command prompt.
13. Logon Windows NT as Administrator with the new password.

If the files system is NTFS, you have two options.

Option1:
1. Connect your HD to a computer with Windows NT 4.0. If Service Pack 5 or later was installed, you may connect it to a Windows 2000 or XP computer. The file system must be NTFS.
2. Follow the above from Step 2. You navigate to X:\Winnt, where X is the drive letter of your HD.

Option 2:
1. Install Windows NT 4.0 in a separate partition. If you have an unpartitioned space in your HD, create a partition and install Windows with NTFS there. Then follow the Step 2 of Option 1.
2. If you do not have unpartitioned space, you need a third party software (e.g. Partition Magic) to resize the partition, create a partition, and then install Windows there. Follow the step 2 of Option 1.