Change security ID

Many IT professionals working in a Windows Operating System environment may be familiar with this error message. I've run into it in cases where my peers tried to forcefully add duplicate virtual machines to the same domain. If you've made the mistake of creating an image without properly sysprepping it first, you'll likely run into this issue. If you'd rather not start all over from the top, the free application, NewSID, is a relatively quick and easy way to generate a new Security Identifier.


In most cases, this is a simple process, but for the sake of not screwing things up worse than they already are, visit the link, "More Info on NewSID" in the Resources section, and make sure that this solution applies to your situation.

Visit the link, "Download NewSID", download it, and extract the files to an accessible location.

Back up your data. Things shouldn't go wrong, but just in case...

Run the file "Newsid.exe", pretend to read the terms and conditions, and "agree" to them.

A screen will come up asking you to back up your data before continuing, but we already did that in Step Three, so continue by clicking "Next". You'll arrive at the Choose a SID window. You can either generate a random SID, copy a SID from another computer, or manually enter one. Unless you have a specific reason to choose options two or three, I highly recommend generating a random SID. Once you've made your selection, click "Next".

You will now be given the option to rename the computer. Although this isn't necessary to change the SID, you may want to do so if there is a PC with an existing name on the network. Click "Next".
The process will now begin. It takes a few minutes as it works through your system

files and your registry making appropriate changes. Once complete, your system will restart.

Once the machine reboots, try logging back in.