You can't print a check; a message says the transaction is unbalanced
Before you can record and print a check, the payment amount must be fully allocated. That is, the total amount of the check (as shown in the check image at the top of the window) must be assigned to the accounts that are being paid for. For example, if you're paying a telephone bill, you might allocate the entire payment amount to your Telephone expense account. Other payments might be split between two or more allocation accounts if you're using a single check to pay for multiple costs that you track separately -- supplies and postage, for example.
When the check amount is fully allocated, the Out of Balance amount near the bottom of the window will be $0.00, and you'll be able to record and print the check.