Cancel Order Email Error

After user login, and clicks to cancel order, there will be an error "Notice
You must provide at least one recipient email address.". How to solve this error, is it an error on setting?

Hi,

Normally, the recipient email address of that email is automatically the email address you have in the "from" setting of the Emails section of the HikaShop configuration.
So the first thing would be to check this.
Also, it's possible it could be not working if you have (or had) a custom field of the table "order" with the column name "email".
In that case, it would override the email from the configuration and you can edit the order cancel via the System->Emails menu and add such code in the HTML version: where xxx is the email address you want to send it to.