How do I disable the prompt for credit card number when tendering a sale with a credit card? We use an external terminal to authorize cards.

First go to Manager | Database | Tenders | <tender type> | Properties | Verification and make sure 'Perform verification via EDC' is unchecked.

Under the General tab, if you set the 'Tender type:' to Credit Card the POS will prompt for card data (number, expiration, authorization code). If you do not want to enter that data during a transaction, change the 'Tender type:' from Credit Card to Other or Cash.

The reason it works this way, even if you are using terminal-based authorization, is so invoices can be linked to the credit card number used. This allows you to match a chargeback with an invoice  (last 4 digits). To implement this feature, you'll need to add a MSR (mag swipe reader).

If you won't be using this feature you may want to create to single tender type called Credit Cards instead of separate entries for each card. Whether you setup a single tender or multiple, remember to set the type under the General tab to Other or Cash to avoid the prompt for more card data.