When I try to print an invoice a box pops up asking for FAX information. I can't get an invoice printed. The print function worked fine yesterday.

Hello there, dat4.

Let's ensure you can print invoices in QuickBooks Online (QBO).

Several causes for the FAX information window popping up include:

• The Printer Setup window opens off-screen.
• The Intuit internal printer is selected as the default printer.
• Damage to the QBprint.qbp file.
• Missing or damaged QuickBooks application files.

To fix this, let's reset the default printer in Windows. Here's how:

1. Click Windows, select Settings (or Control Panel) > Printers and Faxes.
2. In the Printers and Faxes dialog window, right-click on a working printer.
3. Select Set as Default Printer. Close the Windows Printer and Faxes window.
4. Open QuickBooks and open the Printer Setup window to verify changes.

Afterward, shut down your computer and printer, then wait about 15 seconds before powering them on again.

Additionally, I'll be providing the following articles to help manage and personalize your invoices in QBO: 

• Customize invoices, estimates, and sales receipts
• How to record invoice payments manually

Let me know if you've other questions. I'm always here to help. Take care.