Error Code 00: Issuer System Unavailable

Read Time: 3 min

If you’re accepting credit card payments, it’s possible you may come across error code 00 in the process. In an ideal world, the checkout process always runs smoothly. But in reality, some transactions experience hiccups like a declined card or a processing error. When there is a problem, it’s important to know what caused the error and, more importantly, how to fix it. When a payment cannot go through, terminals return one of many credit card decline codes. Each decline, error, or hold code tells you why the payment did not succeed. Read on to find out what an issuer system unavailable message means and how to resolve an error code 00 for your customers.

Issuer System Unavailable: What It Means

The error code 00 may not be as serious as other errors or decline codes. The 00 credit card error code indicates a communication error that is often temporary. Simply put, when you receive error code 00, you should view the code as an indication to retry the payment. The 00 code may be the result of a cashier’s typo or a system error.

If the payment does not go through the second time, it’s a sign of a larger issue and will require you to contact your payment processor. If the processor says the issue is coming from somewhere else, you may need to direct the customer to contact their card issuer (Visa, Mastercard, Discover, American Express, etc.). A 00 error code may appear because of a problem with the credit card processing network or an error with the customer’s issuing bank. It’s impossible to know where the error is coming from by the error code, and will require further investigation.

someone tapping their credit card on a terminal that shows an error code 00

What is an Error Code?

An error code occurs when there is a problem with the checkout process that prevents a successful payment. An error code is not the same as a decline. It just means there was an error somewhere within the payment process. Regardless of the merchant’s chosen credit card machine, a specific error code number will appear any time there is an issue with the checkout process. Learning the meanings of each different error code can help you properly address the problem and further assist your customers.

How to Resolve Error Code 00

When error code 00 appears, it’s best to try the transaction again. You may even need to type the credit card details in by hand rather than swiping, tapping, or dipping the card. Error code 00 can appear if the credit card number was incorrect. In this case, you can resolve the error by double or even triple checking the customer’s account details and trying the transaction again. If the error happens again, you will need to contact your payment processor.

While error code 00 may appear for anything from a typo to a system error, you cannot override it. Instead, apologize to the customer for the inconvenience, call the payment processor, and instruct the customer to contact their issuing bank if you have to. You may also politely request the customer to try another form of payment. Now that you know how to troubleshoot this error code, you’ll know how to help your customer if it appears.

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