Situatie
The program fails to open and shows an error message: “QuickBooks already has a company file open”.
Solutie
1. Restart the computer.
2. Right-click the QuickBooks icon or shortcut, and then click Run as administrator.
3. On the Edit menu, click Preferences.
4. In the left pane, click General, and then on the My Preferences tab, clear the Keep QuickBooks running for quick startups check box, and click OK.
5. Close QuickBooks and restart your computer.