Windows keeps telling me I don't have a default email program

I seen a few times in the eM Client forums that people ask about the “default” issue, but it wasn’t quite the same as what I’m having. 

I’m on Windows 10 and I just switched form Outlook 2010 to eM Client and at random times, I get a notification on my screen about not having a default Email Program (see attachment). I go into the default programs settings and it shows eM Client is my default program, but I still get this error popping up. I have set it as default in the advance settings, I’ve uninstalled and deleted all the registry entries for all email programs and reinstalled it again. I still get the error.
Is there any way to stop this from popping up? It has popped up twice since starting this post. 
Thank you

if the solutions with the registry didn’t help your problem, then I am sorry to say that I do not know what else could. This is an issue with Win 10 and not eM Client, so I suggest contacting Microsoft support.