QuickBooks prompts this type of warning message when the net payment amount of your employee is less than 0 which is not allowed when processing payroll. You must enter an amount at least greater than zero to proceed.
However, if your intention is to create a zero net paycheck for the following reasons below, you can check out this article for the detailed steps on how to do this depending on your reason: Create a zero net paycheck.
Put an entire paycheck into a retirement plan.
Designate an entire paycheck for income tax.
Record a gift made to an employee. Such as cash or a gift card.
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