Is it possible to customize the event.error object?

Is it possible to change the property of the event.error object?

When the following codes are executed, it shows a red window dialog with a " Error occurred. Customer Already Exists" message.

I want to change the header “Error occurred” to be my own message header and the background color of the window dialog. I would like to know the properties of the event.error object so that I can customize the error window?

This is what I have in my codes.

if (response.records.length) {

    event.error = ‘Customer Already Exists’;


Hello annaylee,


Kintone Developer site introduces many ways to create custom pop-up and error messaging.

The following page shows a list of method to create them, so could you check it?


Kintone Developer Program - Pop-ups and Error Messages


I hope this helps.