QuickBooks Error 6000 80 occurs when QuickBooks tried to access the company file. The error comes up during program installation, during windows opening or windows shutdown etc. Damaged .qbw files, could not communicate with the server, data damage on the company file etc. are some of the causes related to this error. Log onto QA Solved.com to resolve the issue. Alternatively, you can speak to an expert QuickBooks support number and amend the issue.