What to know before exporting from QBO to desktop:  https://community.intuit.com/articles/1145409-export-limitations

The “how to”:  http://payroll.intuit.com/support/kb/1000044.html

Resolution for 'before exporting issue: 'QBO file to QB desktop' available: Yes.

The before exporting issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the before exporting issue yourself by looking for a resolution described in the article. If it is a complex before exporting issue or you are unable to solve the issue, you may contact us by clicking here or by using other before exporting support options.

For more information about resolving issues related to before exporting in Quickbooks/QBO or to get support for the issue 'QBO file to QB desktop', click the link below: