I need to change the default program for all users on a terminal server (Windows Server 2008 R2). I have seen another article on SuperUser (How to set default programs for all users on a Windows Terminal Server 2008?) that describes how to do this for a mail client, but it does not go into any details about how to change other default programs for all users. In my particular case, it is the default program used for files with the .PDF extension. The article referenced in the question linked about (https://support.microsoft.com/en-us/kb/186498) does not actually go into details of how to do this, despite what the answer states.
I'm fairly certain there is a registry entry in HKLM that handles this that I can change, but the key in HKCU takes precedent. I learned this from the comments in (where in the registry does Windows store, with which program to open certain file types?)
Does anyone know of a way to handle this? I am comfortable enough with Powershell that I can script it out if I know where to look. Perhaps Group Policy? Thank you in advance.