How to recover or reset domain administrator password of DC running on windows 2008 R2 ?

You can use below two application to reset the password both are tested.

1) http://www.top-password.com/knowledge/reset-directory-services-restore-mode-password.html


2) http://pogostick.net/~pnh/ntpasswd/cd110511.zip

Try this steps here:

http://binarynature.blogspot.co.il/2013/01/reset-active-directory-administrator-password.html

Take a look at this solution How to logon using the expired domain administrator password in W2012 domain

This trick works way down to NT server, although slightly modified.

Thanks for your valuable comments. Issue solved using renaming the utilman.exe to cmd.exe and using netuser command at logon.

Curious then, why did you select the answer that you selected - the Utilman trick was illustrated in the video I told you to watch?

HI Lee,

I did not checked your video, because i resolved the issue before that time. But i appreciate your exact solution. Thanks for the support.

In my opinion, since I posted my comment BEFORE you posted your comment, regardless of how you found the solution, I should be credited with the answer.  Certainly not a post that was NOT in fact your answer.  (This holds true for any post - I don't know if it's a "rule" on EE - but I think it should be - if your solution was posted before you stated the issue was resolved, then the person who posted it deserves the credit).