Subject: PsPasswd
Posted: 21 July 2014 at 5:11am
We cannot help you with this.
Before PsPasswd can change a password you must provide required login credentials. This is not a limitation of the software but imposed by Windows security. The ability to change a password without credentials would be an enormous security problem.
What you are asking for is considered hacking and is not permitted by forum rules. You may have a legitimate reason but we have no way to verify this. Also be aware that this is a public forum where all posts will be accessible by anyone with an Internet connection for years to come. Some of these people will have dishonest intentions. Thus we must err on the side of caution.
You will have to work out your issues with your sister by other means.