Key Takeaways
- "Discovered — currently not indexed" is the most common and misunderstood GSC status — it means Googlebot found the URL but hasn't crawled it yet, usually due to crawl budget prioritisation, not a technical error; the fix is to improve internal linking to high-priority pages
- Coverage errors showing "Crawled — currently not indexed" signal that Googlebot visited the page but decided not to index it — the most common causes are thin content, duplicate content, or a noindex tag on a page you intended to be indexed
- Core Web Vitals "Poor" and "Needs Improvement" URLs in GSC reflect field data (real user measurements via CrUX), not lab scores — a page can score green in PageSpeed Insights but still appear in GSC CWV failures if real users on slow connections experience poor LCP
- Structured data errors in GSC → Rich Results Test are genuinely blocking rich result eligibility — a "Valid with warnings" status means warnings only (eligible for rich results), but "Error" status means the schema failed validation and the page won't get the rich result
- The URL Inspection tool in GSC is the fastest diagnostic for any single-page mystery — it shows the last crawl date, the rendered HTML Googlebot saw, the canonical Google selected, the index status, and any coverage issues specific to that URL
Coverage and Indexing Errors
GSC → Indexing → Pages shows all URLs Google knows about, with their current status. Key statuses to fix:
"Crawled — currently not indexed" — Google crawled the page and chose not to index it. Most common causes:
- Thin or duplicate content (Google found similar content on other pages and chose not to index the duplicate)
- Low-quality signals (the page is too short, too sparse, or provides little value vs existing indexed content)
- A noindex tag that shouldn't be there — verify with URL Inspection
Fix: Use URL Inspection on the specific URL to confirm no noindex tag is present, then improve content quality. If the page is intentionally thin (e.g. a tag page), consider whether it should be indexed at all.
"Discovered — currently not indexed" — Google found the URL (via sitemap or link) but hasn't crawled it. This is a crawl budget issue, not a technical error.
Fix: Improve internal linking to the affected page by adding links from high-authority pages that get crawled frequently. Ensure the page is in your sitemap and remove orphan pages (pages with no internal links pointing to them).
"Redirect error" — a URL redirects incorrectly (redirect chain too long, redirect loop, or redirect to a 4xx page).
Fix: Use the Redirect Tracer tool to map the full redirect chain for the URL; fix the redirect to point directly to the final destination.
"404 (Not Found)" — the page was previously indexed but now returns 404.
Fix: If the page still exists at a different URL, 301 redirect the old URL to the new one. If the page no longer exists, check whether any internal or external links still point to it — update those links.
Core Web Vitals Errors
GSC → Experience → Core Web Vitals shows pages with Poor and Needs Improvement ratings based on CrUX (Chrome User Experience Report) field data. Because this is real-user measurement data, a page can score green in a lab test like PageSpeed Insights and still appear here if actual visitors on slower connections or devices experience poor performance.
LCP (Largest Contentful Paint) — "Poor" (>4.0s)
Most common causes: render-blocking CSS or JS delaying the LCP element, hero images not preloaded (missing <link rel="preload"> on the LCP image), images served without size optimisation, slow TTFB (server response time).
Fix steps:
- Identify the LCP element using PageSpeed Insights → Diagnostics → "Largest Contentful Paint element"
- If it's an image: add
<link rel="preload" as="image" href="...">in<head>, ensure the image hasfetchpriority="high", serve WebP format, and size it correctly for the viewport - If TTFB is slow (>600ms): investigate server response time — check caching, CDN configuration, or server-side rendering latency
CLS (Cumulative Layout Shift) — "Poor" (>0.25)
Most common causes: images without width and height attributes (browser can't reserve space before the image loads), ads injected above content, web fonts causing layout shift (FOIT/FOUT).
Fix: Add explicit width and height attributes to all images. Add font-display: optional or font-display: swap to @font-face rules. Use CSS aspect-ratio on containers for dynamically-sized content.
The Page Speed Inspector checks for images missing width and height attributes and lazy-loaded images above the fold — two of the most common sources of LCP and CLS issues that show up in GSC Core Web Vitals reports.
Structured Data Errors
GSC → Enhancements shows rich result types detected on your site (FAQPage, HowTo, Review, etc.) and their validation status.
Status: Error — the schema failed validation and the page is ineligible for the rich result. Common errors:
- Missing required field (e.g. FAQPage missing
@type: Questionon question items, HowTo missingstepitems) - Wrong value type (e.g.
datePublishedvalue not in ISO 8601 format:2026-06-22T10:00:00Zis correct;June 2026is not) - Empty required field
Fix: Use URL Inspection → Rich Results Test for the specific page to identify the exact field causing the error. Fix the JSON-LD and retest.
Status: Valid with warnings — the schema passes all required fields but is missing recommended fields. This does not block rich result eligibility, but adding recommended fields improves how the rich result is displayed in search.
The Schema Markup Tester validates JSON-LD, Microdata, and RDFa against 18 schema types — showing exactly which required and recommended fields are missing or incorrect on any URL before you submit a fix to GSC.
Manual Actions
GSC → Security & Manual Actions → Manual Actions. If anything appears here, a human Google reviewer has flagged a guidelines violation on your site. Manual actions are rare and serious — they are applied when the violation is intentional or severe enough that algorithmic signals alone don't handle it.
Common manual actions include unnatural links (buying or selling links), thin content with little or no added value, cloaking (showing different content to Googlebot vs users), and user-generated spam.
Fix: Address the specific violation described in the action, then submit a reconsideration request through GSC. Google typically responds within a few weeks. See our Google Core Update Recovery guide for the full reconsideration request process.
Using URL Inspection for Diagnosis
For any page that is behaving unexpectedly in search, URL Inspection is the fastest first step.
- Open GSC → URL Inspection → paste the URL
- Check "Coverage" — what is the index status? What was the last crawl date? If the page was never crawled, check internal linking and whether the URL is in your sitemap
- Check "Enhancements" — are there structured data errors on this URL specifically?
- Open "Inspected page" → "View crawled page" to see the rendered HTML Googlebot stored — this reveals whether JavaScript-rendered content was actually indexed
Request indexing after fixes: URL Inspection → "Request Indexing" prompts Google to recrawl the URL within a few days rather than waiting for the normal crawl schedule. This is useful after fixing a noindex tag, correcting a canonical, or publishing new content you want indexed quickly.
Common GSC Error Workflows
| GSC Error | Most Likely Cause | First Diagnostic Step |
|---|---|---|
| Crawled — currently not indexed | Thin or duplicate content | URL Inspection → confirm no noindex; check content quality |
| Discovered — currently not indexed | Crawl budget / orphan page | Check internal links to the page; add to sitemap |
| Redirect error | Redirect chain or loop | Redirect Tracer → map the full chain |
| LCP Poor in CWV report | Unoptimised hero image or slow TTFB | PageSpeed Insights → identify LCP element; Page Speed Inspector → check TTFB |
| Schema Error in Enhancements | Missing required field in JSON-LD | URL Inspection → Rich Results Test → identify field |
| Manual action | Guidelines violation | Read the action description in GSC; fix the specific issue |
Find the Technical Issues GSC Flags Before Google Does
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