Error 80040438 - Multiple QuickBooks Running

Modified on Sun, 26 Jul at 3:07 AM

Overview

The QQube synchronization log contains an Intuit Software Development Kit (SDK) error similar to the following:

Synchronization log message

<<<<<<<<<<<<<<<<<<<<<< 10/15/2027 06:44:57 PM >>>>>>>>>>>>>>>>>>>>>>
BeginSession
Error Code: 80040438
The application trying to connect to QuickBooks is not supported
while multiple instances of QuickBooks are running.
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<

What the Error Means

Error 80040438 comes directly from the Intuit SDK. QQube cannot communicate with QuickBooks while two instances of QBW32.EXE are running under the Windows user where the synchronization occurs.

Where the Problem Occurs

Environment	Windows User to Check
Single-User workstation	The Windows user currently running QQube and QuickBooks.
Multi-User server	The dedicated Windows synchronization user where QQube was installed.

QuickBooks may allow two company-file windows to be opened manually, but the Intuit SDK cannot operate while multiple QuickBooks instances are running.

Resolution

1. Close All QuickBooks Instances

Under the Windows user where the QQube synchronization runs, close every open QuickBooks window.

2. Check Windows Task Manager

Open Windows Task Manager and confirm that only one instance of QBW32.EXE is running.

If more than one instance remains, close the extra QuickBooks process before starting the synchronization again.

Expected Result

Only one QuickBooks instance is running under the QQube synchronization Windows user, and the synchronization completes without Error 80040438.