An internal QuickBooks error occurred while trying to access the QuickBooks company data file

Sign into QuickBooks as admin

Problem

You cannot sync with QuickBooks Desktop

Description

The web connector shows authentication failed and the web connector is red. Here is the error:

An internal QuickBooks error occurred while trying to access the QuickBooks company data file

Solution

Single User Mode

Log into your QuickBooks company file. Select single user mode. Sign in as admin. Run your web connector.