What makes something P0
A P0 failure is a confirmed condition that prevents important content from being safely crawled, indexed, understood, or trusted. It is not a high score on an SEO tool. It is not a warning. It is a blocker — something actively costing you visibility, revenue, or trust right now.
In every SunmosLab audit, we check for these 15 failures before anything else. If one exists, nothing else matters until it's fixed.
The 15 failures
1. Sitewide or template-level noindex
Important pages — homepage, products, categories — carry a noindex directive, usually because a staging setting or plugin option was copied into production. The pages look fine to you. Google is told to ignore them entirely.
Check: Search Console URL Inspection, crawl data, source HTML. Fix: remove noindex, confirm the page returns 200, is not blocked by robots.txt, has the correct canonical, and is in the sitemap.
2. Important pages blocked by robots.txt
Broad rules block product folders, category pages, or the CSS/JavaScript files Google needs to render the page. Remember: robots.txt controls crawling — it is not the way to remove an already-indexed URL.
3. Incorrect sitewide canonical tags
Every page points to the homepage. Product pages point to a category. Country pages point to the wrong country. After a migration, new URLs point to old ones. The canonical tag is supposed to say "this is the official version" — when it lies, Google picks for you, and it often picks wrong.
4. Migration or redesign redirect failure
Old URLs return 404, redirect to the homepage (never do this), create chains (A→B→C→D), or loops (A→B→A). After a redesign or domain change, every important old URL needs a direct, permanent redirect to the closest relevant new URL.
5. Widespread server errors or unavailability
Important pages return 500, 502, 503, timeouts, DNS errors, or certificate errors — sometimes intermittently, which makes them harder to catch. Check from multiple locations, not just your own browser.
6. Production site behind authentication
The live site — or a key section — requires login, a password, VPN, or IP allowlisting. A development password left on. Public pages must be publicly accessible; private content should stay private, but never expect private content to support public search visibility.
7. Hacked pages, malware, or injected spam
Spam pages, hidden links, malicious redirects, fake login forms, foreign-language spam you never wrote. If your site is compromised, everything else is secondary.
8. Manual action or spam-policy violation
Search Console shows a manual action, or the site uses cloaking, hidden text, doorway pages, scaled low-value content, fake structured-data reviews, or link schemes. Read the exact issue, fix it genuinely, document changes, then submit reconsideration.
9. JavaScript failure hides the main content
The browser displays your product details, prices, and descriptions. Google's rendered version doesn't contain them. Compare raw HTML with browser-rendered HTML — if critical content only appears after JavaScript runs, and the JavaScript fails or is blocked, the content doesn't exist for search.
10. Important content only behind interaction
Key content appears only after clicking "load more," opening a tab, scrolling, submitting a form, or accepting a consent prompt. Interaction should improve convenience — never be the only way to access content that matters.
11. Accidental mass deletion or URL removal
A deployment removes product pages, category pages, or important internal links. Compare your current crawl against your sitemap, Search Console top pages, and analytics landing pages. Restore or redirect what's missing.
12. Wrong domain, protocol, or environment indexed
Search engines index your staging domain, an old domain, the HTTP version, or both www and non-www versions. Secure private environments, fix canonicals and redirects, and consolidate to one authoritative version.
13. Redirect loops or long chains
HTTP → HTTPS → www → non-www → new URL. Each hop loses link equity and crawl budget. Use one direct redirect to the final preferred URL.
14. Major e-commerce catalog failure
Products marked out of stock when they're not. Wrong prices or currencies. Duplicate variant URLs. Category pages blocked. Product structured data broken. Product content only available through JavaScript. Check your best sellers and highest-revenue landing pages first.
15. Local or international targeting failure
Wrong address, phone, hours, or service area. Closed locations presented as active. All country pages canonicalized to one. Broken hreflang. Wrong currency or shipping info. Automatic redirects that prevent access to other locale versions.
What's usually NOT P0
These matter, but they don't block your store from being found:
- Missing meta descriptions
- Slightly long title tags
- A low Lighthouse score without real-user impact
- Missing optional structured-data properties
- A small number of broken internal links
- Low word count on a low-value page
- A third-party toxic-backlink score
- Minor image compression opportunities
If an agency leads with these as "critical," ask what they're actually blocking.
The triage order
When multiple P0s exist, fix them in this order:
- Secure the site and check for manual actions
- Restore availability and resolve server failures
- Remove accidental authentication or environment restrictions
- Restore crawling and indexing of important pages
- Repair migration redirects and canonical signals
- Restore missing pages, content, and internal links
- Fix JavaScript rendering or hidden critical content
- Correct e-commerce, local, or international data
- Recheck Search Console, crawl data, and important URLs
- Move to P1 improvements only after P0s are contained
How we use this: every SunmosLab audit opens with this exact P0 scan. If your store has one of these failures, it's the first thing in your report — with the evidence, the date, and the fix. Start with a $400 audit or book a free call. Not sure your store is even indexed? Start with the 2-minute diagnosis.