I could access my chess games on my samsung phone by clicking on the last challenge I received from the website , but now all of a sudden my phone responds with "No app to open this." I am using Outlook.
Any idea where I can start looking for a problem?

Maybe inadvertently I was using an app of some sorts, but I have no idea what app, to maybe re install?

@pawnpaw

There is an RHP app for smartphones, if you do not wish to use the web browser. It's free.

https://play.google.com/store/apps/details?id=com.netadapt.redhotpawn&hl=en&gl=US

@moonbus
I forgot about that option.
Sorted.
Thanks.