QB Issue Resolution:
QuickBooks never does this on its own.
This happens when you mark them all in the 1099 wizard, and without warning. There is no undo. It seems to be a common mistake.
Resolution for Issue 'why did quickbooks change all of my vendors to needing a 1099' available: Yes (Solved).
Source: Intuit Community forum.
why did quickbooks change all of my vendors to needing a 1099: this 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 issue yourself by looking for a resolution described below. If it is a complex issue or you are unable to solve the issue, you may contact us by clicking here or by using other support options.Support for 1099
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Error Recovery for 1099 [Canada]
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