Apple Watch Ultra 3 Action Button errors with WatchOS 26

Can you start other apps by using the Action button?

In case not, unpairing the watch and setting it up as a new watch, without using the latest backup, would be a way to rule out a software issue.

If this does not work, getting the watch diagnosed by Apple or an Authorised Apple Service Provider would be the next step.

Unpair and erase your Apple Watch - Apple Support

Apple Watch Service and Repair - Apple Support

Apple - Find Locations

You should let Apple Techs know directly about this issue by using the Feedback link, as this is the only way to reach them. The more users do that, the more likely this issue will be corrected.

Feedback - Apple Watch - Apple

It happened to me this morning, starting my 3rd party workout using the Action Button on my Ultra 2.

I guess, since this did not happen before watchOS 26, it is software related after all.

Since the latest watch OS update the action button no longer launches workout app. For two or three years now I have been able to launch a workout (usually indoor cycling). Suddenly after the last software update the launch workout action freezes.

I finally rebooted the watch and sense then thing have worked as I think they are supposed to. Hopefully it will stick. I hope I am using the proper name for the button. It is the orange button on the side opposite the crown.

same here

Glad, that the Force Restart helped 🙂

Yes, the orange button on the left side of the watch is called the Action Button.