QuickBooks unable to send invoices error might not allow you to send an invoice or statement to the customer.

Incorrect email preferences.
QuickBooks not installed properly.

To get rid of QuickBooks unable to send invoices error, you need to install QuickBooks again after getting it uninstalled from the control panel.

Get quick and perfect assistance in fixing QuickBooks unable to send invoices, reach out to QuickBooks enterprise support at +1-888-485-0289 or visit here: https://www.quickbooksenterprisesupport.com/simple-steps-to-fix-quickbooks-unable-to-send-invoices/