It isn’t clear what “backward” part you intend to use.
The 2009 files will need to have interim updates, to be used in QB 2017. There is no going Backwards with the updated file.
Resolution for 'backward compatible issue: 'Is QuickBooks 2017pro backward compatible to 2009 pro using windows 7 spc1' available: Yes.
The backward compatible 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 backward compatible issue yourself by looking for a resolution described in the article. If it is a complex backward compatible issue or you are unable to solve the issue, you may contact us by clicking here or by using other backward compatible support options.
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