Why troubleshooting steps on how to fix issues when QuickBooks 2021 Won't Not Opening. However, sometimes you might face the scenario where you unable to open the accounting software on your system. This is a frequently seen issue after . Reasons if “QuickBooks Unable To Open The Company Files”. There can be plenty of factors which causes company file not opening. What happens when QuickBooks 2021 does not Opening? You have clicked on the of a company file or the QuickBooks 2021 Not Opening Desktop option, but the program does not start. Solutions for when QuickBooks 2021 Not Opening.