Setting Default Applications and File Associations

1. Log onto your Reference VM as normal.
2. Set the default applications as you prefer using the Settings menu.
3. Create a temporary folder, e.g. C:\Temp
4. Open a Command Prompt, as Administrator.
5. Run the following Command:
   Dism /Online /Export-DefaultAppAssociations:C:\Temp\AppAssoc.xml
6. Shutdown your Reference VM, and capture your image as you normally would.
7. Create or Edit an Answer File, and click Advanced Settings.
8. On the Tasks tab, click Add.
9. Toggle the Phase drop-down menu and select First boot as system.
10. In the Command line field, type the following command;
    Dism /Online /Import-DefaultAppAssociations:C:\Temp\AppAssoc.xml
11. Click OK.
12. Adjust any other settings as needed and click OK to close the Advanced Settings window.
13. Click Next to step through the Answer File Wizard to apply or change any other Answer File settings.
14. Click Finish and save the Answer File. 
15. Create new Boot Media with your new Answer File, and deploy your image.

Note: Due to sysprep, the default applications set will not apply to any existing user account profiles on the Reference VM after deployment is complete. Log onto the device with a new domain account, or create a new local user account to confirm that the default applications were set correctly.