QuickBooks POS - Invalid Input Error

Hello, @TEgolf.

Usually, when entering a code or keyword on the Scan or enter item information section on the Sales Receipt page, the lists of items will automatically show up on the drop-down. Since you're experiencing issues while working with your sales receipt, I recommend repairing your QuickBooks Desktop Point of Sale. For the steps, you can check it here: Repair QuickBooks Desktop Point of Sale.

If you're getting the same experience, you may need to get in touch with our Support Team. This way, they'll be able to check and investigate this further securely.

For the support's contact information, you can check it here: QuickBooks Point of Sale Support.

Keep posted if you have any other questions. I'll be right here to help!

Make a backup of the data.

Install the software and restore the backup on a different computer.

If it works fine on another computer, the store computer is the issue.

 If you get the same behavior on both systems, and changing the date on the system causes the issue to go away, the company data is damaged and would need to be fixed by Intuit Data Services.