If you’re seeing QBWC1039 or other Web Connector connection errors such as “Could not start QuickBooks” or “Maximum connection retries exceeded" while connecting Sage Expense Management to QuickBooks Desktop through Web Connector, you’re not alone.
These errors typically occur due to company file conflicts, permission or session issues, incorrect QuickBooks state (multi-user mode, background prompts), or mismatches in how QuickBooks and Web Connector are run. In this guide, you’ll find a consolidated breakdown of all known Web Connector error variants, what causes them, and exactly how to fix each one.
Best Practices to Avoid QBWC Errors
Before we dive into fixes, follow these up-front best practices to minimize the risk of QBWC errors and ensure smooth integration with third-party applications:
Prepare your company file and open Web Connector
Before starting, close all open QuickBooks Desktop windows and any existing Web Connector sessions.
Open QuickBooks Desktop as Admin and switch to Single-user mode.
Open only the correct company file you plan to integrate (ensure no other company files are open).
Once QuickBooks is fully open and idle, right-click the Web Connector icon and choose Run as Administrator.
This ensures Web Connector connects to the intended company file and avoids file-mismatch or session-related errors.
Check file placement
For local setups: Store both the
.qbw(company file) and.qwc(integration file) on the same computer that runs QuickBooks and Web Connector.For hosted setups (e.g., Right Networks, Ace Cloud): Upload both files to the same hosted environment and place the
.qwcfile in the same folder (or close to) your.qbwfile.
Keep files stable
Avoid renaming, moving, or relocating the company file.
If you must, create a new
.qwcfile to reflect the updated name or location.
Manage app entries carefully
Remove old or duplicate app entries before adding a new
.qwcfile (both in QuickBooks and Web Connector).Add each .qwc file only once per company file to prevent duplicate errors.
Grant permissions
In QuickBooks, go to Edit → Preferences → Integrated Applications, and ensure the Sage Expense Management integration app is allowed access.
Maintain good backups
Always keep a recent local backup of your company file before making major changes or redoing the integration.
QBWC1039 Error types and fixes
Error: “QBWC1039: Error connecting to QuickBooks. Error message received from QuickBooks was…”
Cause: Web Connector and the company file are located in different directories.
Fix:
Locate your QuickBooks company file (press F2 or Ctrl + 1 inside QuickBooks to view location).
Make sure Web Connector is running from the same directory as the company file.
Error: “If the QuickBooks company data file is not open… BeginSession must include name of data file”
Cause:
Company file was renamed or moved.
Web Connector isn’t set to run when QuickBooks is closed.
Fix:
If the file was renamed or moved:
Restore the original name and/or move it back to its original location.
Reopen the file in QuickBooks.
If using a third-party app, notify the vendor to update their file reference.
If Web Connector isn’t configured to run in background:
Sign in to QuickBooks as Admin.
Go to File → Switch to Single-user Mode.
Navigate to Edit → Preferences → Integrated Applications → Company Preferences tab.
Select the app → click Properties.
Check Allow this application to log in automatically.
In the authorization window, select YES, choose the user, and click OK.
Error: “There was a problem adding the application. Check QBWCLog.txt for details”
Cause:
Company file was renamed or moved.
Your system has older QuickBooks versions that are not updated.
Fix:
Move the file back to its original name/location.
If renaming/moving is needed:
Remove the app from Web Connector.
Rename/move the file.
Reconnect via QWC.
Ensure all versions of QuickBooks Desktop installed on your system are updated.
Example: If you downgraded from QB 2021 to QB 2020, you still need to install and update QB 2021 to the latest release—even if not used.
Error: “This application does not have permission to access the QuickBooks company data file…”
Cause: The QuickBooks Admin hasn’t granted the necessary access permissions.
Fix:
Sign in to QuickBooks as Admin.
Go to File → Switch to Single-user Mode.
Navigate to Edit → Preferences → Integrated Applications → Company Preferences tab.
Uncheck the box labeled “Don’t allow any applications to access this company file.”
In the SDK App Authorization popup, click Yes.
Verify that your third-party app is selected and access is allowed, then click OK.
Error: “This application has not accessed this QuickBooks company data file before”
Cause: QWC file was added without signing in as Admin.
Fix:
Open QuickBooks.
Sign in as Admin in Single-user Mode.
Launch Web Connector.
Click Add an Application, then choose your QWC file.
Error: “Unable to add FileID to company file for this Application”
Cause: The app was added too many times to the same file. This error indicates excessive duplication of the FileID record.
Fix:
You’ll need to contact QuickBooks support for a deeper resolution to remove hidden IDs.
Error: “Unique OwnerID/FileID pair value required”
Cause: The app was already added before, and you're trying to add it again without clearing its record.
Fix:
Option 1: Use the CP3 Tool (Recommended)
Download and open the CP3 Tool.
In the tool, click Open, then select your
.QWCfile.Enter the QBC file location if needed.
Click Remove Stamp.
Confirm all popups:
Click Yes on the QuickBooks Application Certificate window.
Click Continue → Done → OK.
Close the CP3 tool, reopen QuickBooks and Web Connector, and re-add your app.
Option 2: Edit the QWC File Manually
Alternatively, manually edit the QWC file using a text editor (like Notepad):
Open your
.QWCfile in a text editor (e.g., Notepad).Locate the <
OwnerID> and <FileID> tags.Modify each by changing at least one character to ensure uniqueness. For example:
Original:
<OwnerID>{12345678-1234-1234-1234-1234567890ab}</OwnerID><FileID>{abcdefab-cdef-abcd-efab-cdefabcdefab}</FileID>
Modified:
<OwnerID>{22345678-1234-1234-1234-1234567890ab}</OwnerID><FileID>{bbcdefab-cdef-abcd-efab-cdefabcdefab}</FileID>
Save the modified QWC file.
Reopen QuickBooks and Web Connector, and re-add your app.
Why this matters:
<
OwnerID> and <FileID> are UUIDs (Universally Unique Identifiers) that QuickBooks Web Connector uses to track integrations.Even a single character change makes the pair unique.
This ensures QuickBooks treats it as a new integration, avoiding the QBWC1039 duplication error.
Do this only when:
The company file was renamed or moved, and the integration wasn’t updated.
The same .qwc file was added more than once, causing a duplicate-ID error (e.g., QBWC1039, QBWC1085).
The integration was deleted and re-added, but the old app entry is still showing under Integrated Applications.
Additional Web Connector error variants you may see
You may encounter one or more of the following messages in the Web Connector or QBWC logs:
“Error connecting to QuickBooks”
“Received another company file..”
“Could not start QuickBooks”
“Maximum connection retries exceeded”
These errors often appear together or interchangeably across retries.
Cause:
One or more of the following is true:
QuickBooks Desktop is not running, not fully initialized, or is stuck in the background.
QuickBooks is opened with a different company file than the one expected by the integration.
Another QuickBooks session or user already has a different company file open.
QuickBooks is running in multi-user mode, or a modal prompt (login, update, restore, certificate) is blocking startup.
Web Connector and QuickBooks are not running with the same permission level (Admin vs non-Admin).
Fix:
Fully close QuickBooks Desktop and Web Connector.
Open Task Manager and end all QBWC related processes.
Reopen QuickBooks Desktop:
Right-click → Run as Administrator
Open only the intended company file
Switch to Single-user Mode
Ensure QuickBooks is fully open and idle (no popups or dialogs).
Reopen Web Connector:
Right-click → Run as Administrator
Click Update Selected.
Ensure no other users, RDP sessions, or background QuickBooks instances are accessing a different company file on the same machine.
Confirm that QuickBooks Desktop and Web Connector are installed and run on the same machine/environment (especially for hosted setups).
Need More Help?
If you've tried all the above steps and are still running into errors, don't worry—we're here to help. Reach out to us at [email protected] and our team will assist you.