To share my 2 cents worth, Media Center needs to be closed when making codec settings changes.
1st of all, you should know that I do not test anything Media Center related in Windows 10.
That being said, save your current codec configuration by going to the Misc TAB and choose to [Save ALL Settings]
after doing the below testing, you can easily revert to the saved settings by using [Restore settings]
For Media Center usage, It is always best to use the [RESET ALL] button as your 1st step.
Try using the [x] WMP suggested settings checkbox next (you should know that this setting disables the Microsoft Audio decoder)
The next suggestion (for playback ability) is to disable the Microsoft Video decoder on the Swap Tab
you probably already know that doing this will break LiveTV playback but it can improve file playback.
You may need to sign out of Windows and make this setting immediately after logging back in to get past the FILE IN USE error message.
It is easy to revert this setting simply by unchecking the box.
For those leary of codecpacks and installers, I also release portable codecs without an installer.