# Retool: App page loads returning 521 errors and failing to load for some users

- Impact (vendor’s label): major
- Status: resolved
- Started: 2021-09-21 17:10 UTC · Resolved: 2021-09-21 18:00 UTC · Duration: 50 min
- Updates: 1
- [Vendor status page: https://status.retool.com/incidents/h4tlz9x90yf9](https://status.retool.com/incidents/h4tlz9x90yf9)
- [Company: Retool](https://rewindex.com/company/retool.md)

## Timeline of updates

- **resolved** 2021-09-21 18:00 UTC: We have confirmed our workaround has resolved this issue and are continuing to engage Cloudflare support for a root cause on their end.

_From the vendor’s published history: only the final update text is available for incidents before Rewindex began polling this page._


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Canonical: https://rewindex.com/company/retool/incidents/h4tlz9x90yf9 · Markdown: https://rewindex.com/company/retool/incidents/h4tlz9x90yf9.md · JSON: https://rewindex.com/api/v1/companies/retool/incidents/h4tlz9x90yf9 · Generated 2026-10-18T12:34:56.571Z