ADMT stands for Active Directory Migration Tool and is used to migrate AD objects (such as users, groups, computers, etc.) from one AD forest or domain to another, supporting complex scenarios in the process.
Why Microsoft hides their most useful tools is a mystery though. So here are the download links. You will need to accept some EULAs and have a Microsoft Account if you wish to download it though.
The download links work again, and, because it's not allowed to distribute the packages, I've taken down the mirror link.
Apparently, the download links for PES are no longer working: I've temporarily uploaded it here for those that need it urgently:
→ Password Export Server (PES) - x64 (mirrored) (MD5: 5e8d84152252d0b756be6d3216f16f08)