The only way I can find is to check each vendor and customer individually

when you select a vendor, use the gear at the top right of the list and check mark attachments, that will put a column up that will show you whether there is an attachment or not.  Same […]

Resolution for 'attachment attached issue: 'IN :I want to see all the entries for which there is no attachment attached' available: Yes.

The attachment attached 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 attachment attached issue yourself by looking for a resolution described in the article. If it is a complex attachment attached issue or you are unable to solve the issue, you may contact us by clicking here or by using other attachment attached support options.

For more information about resolving issues related to attachment attached in Quickbooks/QBO or to get support for the issue 'IN :I want to see all the entries for which there is no attachment attached', click the link below: