Android tablet shows strange message?

[Hi y´all !]

At intervals my Android tablet flashes the following message: "The process android.process.acore has stopped unexpectedly. Please try again."
I don't have a clue what that means and what I should do. Most apps - like Wordfeud - still work, but the yahoo.mail app doesn't.
I've tried to reset, but to no avail.
Please help.

[Elaine]

What was the last app you installed before this started happening?
It can range from various apps like hotmail, whatsapp, facebook, or any other messenger apps. Uninstall any recent apps you installed and see if the error goes away. You can try to reinstall and see if the error persists.

Edit: If it does persist, you should consider replacing the app you removed for something else.