create a association reference file from one of the PC, then apply this to all other PCs:

 

  1. Make sure you configured the association on PC A is correct, then user following command to export the association file: dism /Online /Export-DefaultAppAssociations:c:\tmp\defaultFileAsso.xml
  2. Copy this file to a shared drive or deploy this file to a system folder
  3. Open up the Group Policy MMC (open a command prompt and type gpedit.msc) on your Server 2012 instance.
  4. Locate the policy under Computer Configuration\Administrative Templates\Windows Components\File Explorer\Set a default associations configuration file. This policy specifies the path for the XML file that can be either stored locally or on a network location. Enable the policy, and specify the location where you have stored the XML file. The corresponding registry entry is HKLM\Software\Policies\Microsoft\Windows\System\DefaultAssociationsConfiguration.
  5. Link this GPO to the OU where the target PCs are sitting.
  6. Restart the PCs, and check if they are working.