Why does this happen when I press Back?

The previous page was loaded via POST. Chrome cannot replay the POST from cache without your confirmation to avoid duplicate submissions.

How do developers prevent this?

Implement Post/Redirect/Get: after processing the POST, redirect with HTTP 303 to a GET page. This makes Back/Refresh safe.

Chrome ERR_CACHE_MISS — Confirm Form Resubmission & Cache Errors

Informationalchrome

Overview

Fix Chrome ERR_CACHE_MISS error which appears when reloading a page that was loaded via POST request, preventing form resubmission and showing 'Confirm Form Resubmission'.

Key Details

ERR_CACHE_MISS occurs when Chrome cannot serve a page from cache and needs to resubmit a POST request
Most commonly seen as 'Confirm Form Resubmission' dialog when pressing Back or Refresh after a form POST
This is a browser safety feature to prevent duplicate form submissions (double charges, duplicate orders)
Web developers can prevent this with the Post/Redirect/Get (PRG) pattern
Clearing cache may fix persistent ERR_CACHE_MISS on pages that should not show it

Common Causes

Pressing Back or Refresh on a page loaded via form POST submission
Web application not implementing Post/Redirect/Get pattern
Browser cache corrupted, unable to retrieve cached POST response
Browser extension interfering with cache behavior
Service Worker caching strategy not handling POST requests

Steps

1Click 'Continue' in the dialog to resubmit the form (safe for idempotent operations)
2Navigate to the page using the URL bar instead of Back button
3Clear Chrome cache: Settings > Privacy > Clear browsing data > Cached images and files
4Disable extensions temporarily to check for interference
5For developers: implement PRG pattern — redirect with 303 after processing POST