Why does Excel say it can't open my file because the file format or extension is not valid?

Occasionally, when attempting to open up a BidTable or Questionnaire file in Excel, you may receive a message saying that the file cannot be opened because the file format or file extension is not valid.

Typically, this indicates the file has likely been corrupted, or may not be a valid XLS/X document.

To resolve the issue, delete the invalid file, then return to the portal/project where you had downloaded the file, and re-download it.

If you continue to experience errors, please reach out to Bonfire Support!