The Stop button doesn't need any programming in MC to work on a Harmony Remote. If you clear any "Learned Trigger Code" in MC for the Stop button it
should start working again.
However, you have done some non-standard setup on your Harmony, haven't you?
The "STOP" command works from keyboard (CTRL+s), but does not work from Harmony remote for a button that sends CTRL+s.
This does work in MC25.
from
https://yabb.jriver.com/interact/index.php/topic,123399.msg854804.html#msg854804I have used Harmony remotes with Media Center for as long as I've had MC (since about version 16...). Only more recently (version 23 onward), I took the time to program the Keyboard Hot-keys [https://wiki.jriver.com/index.php/Keyboard_Hot-keys] for certain transport controls to the appropriate Harmony Remote buttons (e.g. STOP, SKIP...).
These no longer work in MC26. That is, the Hot-keys still work from a keyboard, but no longer from the any Harmony Remote that has those commands programmed into its buttons. Has anyone else experienced similar anomalies with these? Is there a solution?
So you have probably broken the standard Harmony and MC functionality. It probably worked previously because you had updated the Resource.xml file with the Hot Key you needed.
You need to fix what you changed. Using the standard functionality, as Davelr is, is the easiest solution.