An unknown QuickBooks error code 40003 can appear on your screen when some internal network issue interrupts the payroll update in QuickBooks. 

Running QuickBooks File Doctor will help you to fix the error. Let's show you how to accomplish it without experts' help:

Step 1: Download and Install QuickBooks Tool Hub as the First Step

• The first step involves closing QuickBooks. 

• Now, download QuickBooks' most recent version (1.6.0.3) and save it somewhere you can access it quickly.

• Open the recently downloaded file. 

• Complete the process by following on-screen instructions and agreeing to the terms and conditions. 

• To open the QuickBooks tool hub, double-click on the icon. 

Step 2: The Second Step Involves Running QuickBooks File Doctor 

• Go to the Company File Issues in the tool hub. 

• Select Run QuickBooks file doctor, which can take some time. 

• Now, select your Company File from the dropdown menu. 

• Enter your QuickBooks admin password when prompted on the screen and click on Next. 

Scanning and fixing the error can take some time, be patient, and your network issues with QuickBooks will be resolved.

Checkout : QuickBooks error ps038  |  QuickBooks Error 12152