While QuickBooks Desktop is one of the most trustable programmes on the market, many users experience problems shortly after installing the software on their system. The majority of these errors are related to QuickBooks data file or network configuration, especially when the application is used in multi-user mode. QuickBooks Error 6123, 0 is a common problem that users encounter when opening a company file, usually in multi-user mode, shortly after updating to a new version of QuickBooks. :