Crawl errors are Google's way of telling you something's broken—and ignoring them means wasting your crawl budget whilst preventing perfectly good pages from ranking. When Google's crawler hits a dead end (404), encounters a server meltdown (5xx), or gets stuck in a redirect maze, it simply moves on. Those pages? They vanish from search results.
The good news: most crawl errors fall into three fixable categories, and Google Search Console hands you the exact list of problems. This isn't about becoming a technical SEO expert—it's about diagnosing the top three critical issues, applying straightforward fixes, and requesting validation so Google knows you've sorted it.
By the end of this guide, you'll have investigated your most damaging crawl errors, implemented fixes for 404s and redirects, understood how to monitor server errors, and clicked that all-important "Validate Fix" button. Your site will be cleaner, Google will be happier, and your pages will have a fighting chance of ranking.
What You'll Have When Done:
A clean Search Console Coverage dashboard with critical crawl error validation requested—Google actively re-crawling your fixed URLs.
Time Needed: 45 minutes
Difficulty: Confident (requires basic CMS access and Search Console familiarity)
Prerequisites:
Jump to:
---
Before You Start:
Not sure your internal links are clean? NetNav's Link Audit feature checks every internal and external link in 60 seconds, flagging 404s immediately—a critical step before validating fixes in GSC.
Here's the fastest path to diagnosing and fixing your most critical crawl errors:
Step 1: Open Google Search Console and navigate to Indexing > Pages in the left sidebar. This is your Coverage Report.
Step 2: Click the "Not indexed" tab at the top to filter the report to show only errors preventing indexing.
Step 3: Identify the largest cluster of "Not found (404)" errors. Click on the error type to see the full list of affected URLs.
Step 4: Choose one common 404 URL from the list. Determine if the page moved (needs a 301 redirect) or was deleted (needs internal links removed). Implement the fix in your CMS.
Step 5: Return to Search Console, click the error type again, and click the "Validate Fix" button at the top right.
You've Completed the Quick Version When:
You see a confirmation screen stating "Validation Started" in Google Search Console. Google will now re-crawl the affected URLs over the next 2-7 days to verify your fixes.
✅ Completed the quick version? Move on to Optimize Your Website for Google in 1 Hour or continue below for the detailed walkthrough covering all three error types and advanced diagnosis.
---
Open Google Search Console and click Indexing > Pages in the left navigation. You'll see a graph showing your indexing status over time, with a breakdown below showing different categories.
[MEDIA:SCREENSHOT:gsc-coverage-report]
The Coverage Report showing the status categories (Error, Valid with warnings, Valid, Excluded).
The categories you'll see:
Focus exclusively on the "Not indexed" section first. This is where your critical crawl errors live. The other categories can wait—you're triaging the most damaging issues.
Click on "Not indexed" to expand the list of specific error types. You'll typically see:
The first three are your priority. Let's tackle them in order of frequency.
---
Click on "Not found (404)" in your error list. You'll see every URL Google tried to crawl but couldn't find. This is the most common crawl error—and the most fixable.
[MEDIA:SCREENSHOT:gsc-404-detail]
Inspecting a specific 404 error cluster and showing the linked source pages.
Diagnosing the Source:
404 errors happen for three main reasons:
Click on any URL in the 404 list, then click "Inspect URL" at the top. Scroll down to the "Coverage" section and look for "Referring page"—this shows you where Google found the broken link.
Fix Action for Internal Broken Links:
If the referring page is on your own site, you have two options:
Fix Action for External Broken Links:
If the referring page is on someone else's website, you can't control their link. But you should still redirect the old URL to the most relevant current page on your site—you're capturing that external link equity rather than wasting it.
Pro Tip: Focus on 404s with multiple referring pages first. If ten internal pages all link to the same broken URL, fixing that one redirect solves ten problems at once.
Once you've implemented your fixes (redirects or link updates), return to the 404 error list in Search Console and click "Validate Fix" at the top right. Google will queue those URLs for re-crawling.
---
Click on "Redirect error" in your "Not indexed" list. These are more subtle than 404s—the page exists, but Google got lost following your redirects.
The two most common redirect errors:
Redirect chains: URL A redirects to URL B, which redirects to URL C, which redirects to URL D. Google gives up after 3-5 hops. This often happens when you've moved a page multiple times without updating the original redirect.
Redirect loops: URL A redirects to URL B, which redirects back to URL A. Google gets stuck in an infinite loop and abandons the crawl.
Fix Action:
This is tedious manual work if you have dozens of redirects. Maintaining a strong internal linking structure from the start prevents these issues—but if you're already in redirect hell, fix the errors Search Console flags first, then audit your full redirect list.
Manually checking every crawl error cluster and fixing the broken source links can be highly tedious, especially on larger sites. This is one of the foundational technical checks NetNav runs automatically across your whole site, saving you hours of manual investigation in Search Console reports.
---
Click on "Server error (5xx)" in your "Not indexed" list. This is the most serious error type—it means Google couldn't reach your site at all when it tried to crawl those URLs.
[MEDIA:SCREENSHOT:gsc-server-errors]
Example of a 5xx Server Error report in Search Console.
Why 5xx Errors Are Critical:
Unlike 404s (which tell Google "this specific page doesn't exist"), 5xx errors tell Google "the entire server is broken." If Google encounters repeated 5xx errors, it will reduce your crawl rate—meaning it checks your site less frequently, delaying indexing of new content.
Common causes:
Fix Action:
5xx errors are almost always hosting-related. You can't fix these from your CMS—you need to address server speed or hosting issues directly:
Once your hosting provider confirms the issue is resolved, use the "Validate Fix" button in Search Console. But monitor this closely—if 5xx errors return, you have a systemic hosting problem that needs urgent attention.
---
After implementing fixes for your 404s, redirects, or server errors, you need to tell Google to re-check those URLs. This is where the "Validate Fix" button comes in.
[MEDIA:SCREENSHOT:gsc-validate-fix]
The "Validate Fix" button in Search Console—the final action step.
How Validation Works:
Important: Validation is not instant. Google needs time to re-crawl and re-process your URLs. Don't panic if the error count doesn't drop immediately—check back in a week.
Monitoring Progress:
Return to the Coverage Report weekly and check the "Not indexed" count. You should see:
If validation fails (you get a "Validation failed" email), Google will tell you why. Common reasons:
Go back, double-check your fix, and click "Validate Fix" again.
You've Successfully Completed This Step When:
You've clicked "Validate Fix" for your three priority error types (404s, redirects, 5xx), received "Validation started" confirmation emails, and scheduled a calendar reminder to check progress in one week.
🎉 Completed? You've successfully notified Google of your fixes and established a monitoring routine. Your technical foundation is cleaner than 80% of small business websites. You're ready for Optimize Your Website for Google in 1 Hour—where you'll leverage this clean indexing status to improve your on-page SEO.
---
Common Issues and Fixes:
Problem: The list of errors is massive and overwhelming—I have hundreds of 404s.
Fix: Focus only on "Server Error (5xx)" and "Not Found (404)" first, ignoring the less critical "Excluded" categories. Within 404s, sort by "Number of affected URLs" and tackle the largest clusters first. You don't need to fix every single error—focus on the ones affecting multiple pages or important content.
---
Problem: I fixed the page, but Search Console still shows the error.
Fix: Remember GSC is not instant—it's a historical report. Use the "Validate Fix" button and wait 2-7 days for Google to re-crawl. The error won't disappear from the report until validation completes. Check your email for validation progress updates rather than obsessively refreshing Search Console.
---
Problem: I don't know how to set up a 301 redirect.
Fix: Use your CMS's built-in redirect manager:
If your CMS doesn't have a redirect tool, contact your hosting provider's support—most can set up redirects for you in minutes. Provide them with the old URL and the new destination URL.
---
You've diagnosed your most critical crawl errors, implemented fixes, and requested validation from Google. Your site is now technically healthier, with cleaner indexing and better crawl efficiency. This foundational work ensures Google can actually find and index your content—the prerequisite for ranking.
Next Step: Optimize Your Website for Google in 1 Hour
Now that Google can crawl your site without hitting dead ends, it's time to optimize what it finds. This quick one-hour SEO check-up focuses on your core pages—improving titles, meta descriptions, and basic on-page SEO health to maximize the ranking potential of your newly clean indexing status.
Go Deeper:
---
---
You've just completed technical maintenance that most of your competitors ignore entirely. Fixing crawl errors isn't glamorous—but it's the difference between Google indexing 60% of your site versus 95%. That's dozens of pages now eligible to rank that were previously invisible.
The validation process you've started will run in the background over the next week. Google will methodically re-crawl your fixed URLs, update its index, and—if your fixes worked—move those pages from "Not indexed" to "Valid." Check back in seven days to confirm your progress, then move on to content optimization.
You've successfully cleaned up your technical foundation and validated the fixes with Google. This essential maintenance puts you ahead of most competitors. NetNav can audit your entire site across 9 foundational marketing pillars in 60 seconds—see what other hidden issues (like speed, consistent business details (NAP), or accessibility) need attention before you move on to content strategy.
Start Your Free NetNav Audit →
Previous in sequence
Next in sequence
Other Start Here Guides:
Not sure where to start? Get a free audit of your current online presence and discover your biggest opportunities.
Run Your Free NetNav Audit Now →