QuickBooks error 6123 is nothing but a company file that usually appears at the time when you fail to open it. It is one of the 6000 series errors with 3 or 4 more digits to specify the exact problem. The reasons that might trigger it are outdated QB version, compatibility issues between QB and the company file, corrupt network connection, and many more. Moreover, this also gets encountered when there are any changes to the host computer name. To...