Hi Sharwan Kumarkarn
If you’ve lost the admin password, the most supported way is to use another account that already has admin rights and reset it from there. If you don’t have any other admin accounts, you’ll need to use the Windows Server installation media or recovery tools. Boot from the installation disk, go into Repair your computer - Troubleshoot - Command Prompt, and from there you can enable the built‑in Administrator account or reset the password using command‑line tools. Once you’re back in, you can set a new password for your main admin account.
Another option, if your server is joined to a domain, is to reset the password through Active Directory Users and Computers from a domain controller. That way, you don’t even need to touch the local machine directly. If it’s a standalone server, though, the recovery media route is usually the way to go.
Please notice that avoid third‑party “password reset” tools floating around the internet. They can be risky and unsupported. Stick with Microsoft’s built‑in recovery methods they’re safer and won’t break your environment. Also, once you get back in, it’s a good idea to create a secondary admin account for emergencies, so you’re not locked out again if the main password is forgotten.
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