QBWC1013 ("Could Not Start QuickBooks", 0x80040408)? It's a Permission Setup, Not Corruption

The QuickBooks Web Connector errors with QBWC1013: “Error connecting to QuickBooks. Returning error message to application: Could not start QuickBooks.” (often 0x80040408).

Why “reinstall QuickBooks” is the wrong call: blogspam blames file corruption. The repeatable cause is the Web Connector lacking permission to launch QuickBooks — a few specific setup conditions must be met. Fix those.

Fix 1: Open QuickBooks as Admin, single-user

1. Sign into the company file as the Admin user (not a regular user).
2. File → Switch to Single-user Mode.
3. Leave QuickBooks open while the Web Connector runs.

The Web Connector can’t start a company file the way it needs unless QB is already open as Admin in single-user.

Fix 2: Give the Admin user a password

A blank-password Admin breaks the Web Connector. Set a real password: Company → Set Up Users and Passwords → Change Your Password (or set the Admin password), then reconnect.

Fix 3: Re-grant the app’s access

1. In QuickBooks: Edit → Preferences → Integrated Applications → Company Preferences.
2. Confirm the third-party app is listed and allowed to login automatically. If it’s stale, remove it and re-add the .qwc.
3. Make sure the .qwc file’s company-file path exactly matches the open company file.

Fix 4: Run both at the same privilege level

If QuickBooks runs as administrator but the Web Connector doesn’t (or vice-versa), they can’t talk. Run both the same way (both normal, or both elevated).

FAQ

Is my company file damaged? No — QBWC1013 is a launch/permission condition, not data corruption.

Different QBWC code? For the OwnerID/FileID error see QBWC1039; for the log-file error see QBWC1085; to stop it launching at boot see stop QBWC at startup.

Sources: Intuit — Fix common Web Connector errors in QuickBooks Desktop