You may be here due to the QuickBooks Error code 6210. This is a common QuickBooks error that can be caused by infected or problematic computers. Your computer screen can suddenly appear with a pop-up and obstruct your ability to work freely. Regularly updating your computer and removing junk files are effective ways to keep QuickBooks Error Code 6210, 0 from occurring. The following steps can help you to resolve this error, however. Since you are already experiencing it, follow these troubleshooting steps to resolve it. A QuickBooks error code 6210 usually appears in multi-user mode, and it prevents you from performing any of the tasks. When the QuickBooks download process is corrupt, you can run into this sort of error.