I recently configured “Windows Hello for Business” on Windows 10, which requires the use of a PIN for Biometric Authentication. For configuring the PIN, I used the official Microsoft Docs called: Manage Windows Hello for Business in your organization
This Docs Article explains pretty much all the “Windows Hello for Business” GPO Settings, including the ability to configure the PIN Complexity.
However, when using Group Policy Editor the mentioned “PIN Complexity” Node is not present under “Windows Hello for Business” in the Computer Configuration Section, as shown by the Docs Article.
After my favorite search engine failed me to come up with an answer, I started to explore the responsible Group Policy Template for “Windows Hello for Business” called “Passport.admx”. (“Windows Hello for Business” was called “Microsoft Passport” in earlier Windows Versions)
Inside the XML you find the highlighted line which says:
PIN Complexity moving to the System Node
Switching back to the Group Policy Editor, we can explore the System Node which actually lists the missed PIN Complexity Node. The exact location is: “Computer Configuration\Administrative Templates\System\PIN Complexity”