You’ll need to go to the location where you saved the backup company files, then delete them. Just make sure to delete the file with .QBB extension, and not the .QBW (regular company file).
Resolution for 'backed issue: 'How can I delete old backed up files' available: Yes.
The backed 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 backed issue yourself by looking for a resolution described in the article. If it is a complex backed issue or you are unable to solve the issue, you may contact us by clicking here or by using other backed support options.
For more information about resolving issues related to backed in Quickbooks/QBO or to get support for the issue 'How can I delete old backed up files', click the link below: