QuickBooks cookies are set to a medium level by default. It's a best practice to set the level to "accept all cookies". Enabling cookies will correct issues such as being unable to process payments or credit cards, or log into Merchant Center. Enabling cookies will also correct the following error messages:
"error: You cancelled communication with remote server."
"Payment has failed"
"Problem: You cannot use bank feeds because your company file is not open."
To enable cookies within QuickBooks:
1. Log into your company file
2. Help / Internet Connection Setup / Next / Advanced Connection Settings / Privacy Tab
3. You want the setting to read "Accept All Cookies"
4. You will see a vertical column of short horizontal lines. Either click towards the bottom of that column, or use your wheel mouse to scroll down until the setting changes to "Accept all cookies" (press the Default button if you cannot adjust the setting).