Hello fabfab,
Thank you for posting in Q&A forum.
To better understand your question, please confirm the information below, so that we can help you better.
1.Is your Windows 2019 Server one Domain Controller?
2.Or this Windows 2019 Server is only one member server in one domain?
3.Or this Windows 2019 Server is in only in one workgroup instead of in any domain?
If it is one domain controller, is the screenshot you provided local group policy? Or the screenshot is the picture after you edit Default Domain Policy or any other one GPO?
If it is one member server in one domain and you open local group policy, I think it is normal with grayed out with a padlock in front, no modification possible, because the password policy on domain-join machines is controlled by domain password policy on Domain Controller.
Here is one member server in domain in my lab, when I open local group policy by opening gpedit.msc and click Enter, I will see the same screenshot as you.
I hope the information above is helpful.
If you have any question or concern, please feel free to let us know.
Best Regards,
Daisy Zhou
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