Redirect Chain Too Long — Multiple Hops Before the Real Page Loads
Learn how Scavo measures redirect hops, why chains slow users and crawlers down, and how to flatten protocol, host, and legacy URL redirects into cleaner routes.
Open guideTechnical help for sitewide files, protocol behavior, DNS, and platform hygiene.
Surfacing hidden infrastructure and markup problems before they turn into visible outages or crawl issues.
404 Page Returns Wrong HTTP Status Code
When a deleted or broken URL returns HTTP 200, search engines index it as a real page — polluting your index with dead content and wasting crawl budget. This is called a "soft 404" and Google specifically warns against it. Your 404 page should return a proper 404 status code while still showing a helpful message to users.
Open guideAnalytics Not Installed or Not Firing
Without analytics, every business decision about your website becomes a guess. You can't see which pages convert, where users drop off, which channels drive traffic, or whether changes improve performance. This is the foundation of data-driven optimization — if it's missing, you're flying blind.
Open guideCMS or Server Version Exposed in Headers
When attackers can see you're running WordPress 6.3 or Apache 2.4.51, they can check public CVE databases for known exploits specific to your exact version. Removing version disclosure is simple server hardening — it doesn't fix vulnerabilities, but it removes the signpost that tells attackers exactly where to look.
Open guideCharacter Encoding (UTF-8) Not Declared
Without a declared charset, browsers use heuristics to guess the encoding. This frequently garbles accented characters (é becomes é), em dashes, curly quotes, and any non-ASCII text. For multilingual sites, this is catastrophic. The fix is one meta tag: <meta charset="UTF-8"> before any other content in the head.
Open guideDNS A Record IP Address Changed
DNS A record changes redirect your traffic to a different server. This is expected during hosting migrations, but an unexpected change could mean your domain has been compromised or your hosting provider changed infrastructure without notice. Monitor A record changes to catch problems before users experience downtime or are redirected to malicious servers.
Open guideDomain Registration Expiring Soon
A lapsed domain takes your entire site offline instantly, and recovery can take days even after renewal due to DNS propagation. Worse, expired domains are actively targeted by squatters and spammers who register them within hours. Your search rankings, email delivery, and brand reputation all depend on keeping your domain active. Set auto-renewal and monitor expiry dates.
Open guideEmail Authentication Missing — SPF, DKIM, or DMARC Not Set
Only 18% of the top 10 million domains publish a valid DMARC record, and just 4% enforce a reject policy (Valimail, 2024). Fully authenticated senders are 2.7x more likely to reach the inbox than unauthenticated ones. Meanwhile, an estimated 3.4 billion phishing emails are sent daily, with domain spoofing as the primary vector. Without SPF, DKIM, and DMARC, anyone can send emails that appear to come from your domain.
Open guideFavicon Missing — No Browser Tab Icon
A favicon appears in browser tabs, bookmarks, browser history, and Google's search results. Without one, your site looks unfinished and is harder for users to find among open tabs. It's also a trust signal — professional sites have favicons, and their absence can make visitors question legitimacy.
Open guideHTML Doctype Missing — Browser Rendering in Quirks Mode
Without <!DOCTYPE html> at the top of your HTML, browsers enter "quirks mode" — applying legacy rendering rules from the IE5 era that break modern CSS features like box-sizing, flexbox behaviour, and font rendering. This causes layouts to look different across browsers and makes debugging CSS issues significantly harder.
Open guidehumans.txt Not Found
humans.txt is an optional file that lists who built the site, what technologies were used, and contact information. It's not critical for SEO or functionality, but it's a small transparency signal that helps security researchers reach you, gives credit to your team, and shows you care about web standards.
Open guideHTML Lang Attribute Missing
Screen readers use the lang attribute to select the correct pronunciation engine — without it, they apply default language rules that mispronounce words and ignore language-specific grammar. Browser translation tools also rely on lang to detect when to offer translation. It's a single attribute on the html element that takes 5 seconds to add.
Open guideAbout technical
16 guides
16 active checks
4 sources
Technical hygiene is where silent failures live. Small protocol and infrastructure mistakes can confuse browsers, bots, and operators long before users know why.
This category covers the site-level signals that often sit between product, infrastructure, and marketing ownership. They are not always glamorous, but when they drift you get confusing symptoms: crawlers go quiet, analytics gets less trustworthy, missing pages start looking indexable, or email deliverability drops without a clear application bug to blame.
The value of technical checks is that they expose foundational behavior early. A clean robots file, correct status codes, stable DNS, declared language and charset, trustworthy mail records, and predictable machine-readable resources reduce ambiguity for the systems that interpret your site every day.
Why it matters
These issues often hide in the gaps between teams. No single feature owner may notice them until they have already affected search, deliverability, or operations.
Low-level correctness makes every other category easier to reason about because bots, browsers, and tooling receive fewer contradictory signals.
Common pitfalls
Treating infrastructure files as one-time setup instead of versioned product assets that need review after structural changes.
Assuming the application is healthy because the UI looks fine while status codes, bot guidance, or mail DNS are drifting underneath.
What's covered
Sitewide crawler files such as robots.txt and llms.txt, plus the response behavior around not-found pages and machine-readable routes.
Document-level hygiene such as doctype, charset, language declaration, and favicon discovery.
Where to start
Start with sitewide files and response semantics because those signals affect every page and every crawler immediately.
Then review domain, DNS, and email-trust ownership so infrastructure changes do not happen without a clear audit trail.
