---
metadata:
- name: generator
content: Diplodoc Platform v5.50.6
alternate:
- https://yandex.com/support/webmaster/en/diagnosis/mistakes.md
- https://yandex.com/support/webmaster/tr/diagnosis/mistakes.md
---
> **Documentation Index:** Fetch the complete configuration index at https://yandex.com/support/webmaster/en/llms.txt
# Site errors
If Yandex Webmaster detects issues on your site, they'll appear in **Website optimization** → **Site diagnostics** → **Errors**.
Such errors may lead to the following problems:
- Individual pages or the entire site will disappear from search results.
- Indexing of the site's pages will slow down or decrease in quality.
Checks are performed daily. We recommend fixing errors as soon as possible so that they don't affect the site's availability or presence in search results.
Below is the list of possible errors and instructions on how to fix them.
## Main page returns an error {#main-page}
An error may appear if:
- The page disallows indexing.
- The page redirects somewhere else.
- The hosting security system blocks Yandex's indexing bot.
**How to fix**
To prevent the site’s home page from returning an error:
1. Check the HTML code of the page: if it contains the [noindex directive](https://yandex.com/support/webmaster/en/controlling-robot/metatags.md), remove it.
2. In Yandex Webmaster, go to **Indexing** → **Crawl statistics** and check the page response code in the **Response code** column.
If the response code differs from 200 OK, check whether the problem is currently present using a [server response check](https://webmaster.yandex.com/tools/server-response/).
When checking the server response, pay attention to the **Page content** section. If the tool shows the message saying "Missing page content", check your server settings:
- HTTP header: For example, if `Content-length: 0`, the indexing bot can't index the page.
- Page content size: Must be greater than 0 and match the HTTP header.
3. Wait for the indexing bot to crawl your site, or [submit the page for reindexing](https://webmaster.yandex.com/site/indexing/reindex/).
Your site will be reindexed within two weeks. When the page returns the 200 OK code and its content is available, the warning in Yandex Webmaster will disappear within a few days.
## Failed to connect to the server due to DNS error {#dns-error}
Once a day, the indexing bot accesses [DNS servers](*DNS) to determine the IP address of the site’s server. If the robot doesn't get the site's IP address, it won't index it. The site won't be added to search results.
**How to fix**
Troubleshooting depends on the error:
#|
|| **Reason** | **Solution** ||
||
The DNS records on the site are configured incorrectly, so the indexing bot can't get the IP address. As a result, the site is not indexed by Yandex and doesn't appear in search results.
|
[Check](https://webmaster.yandex.com/tools/server-response/) the correctness of the server response to the indexing bot. If the site remains unavailable, contact your hosting provider to check the DNS records. Once the errors are fixed, the information in Yandex Webmaster will be updated within a few days.
||
||
A short-term problem with accessing the site.
|
[Check](https://webmaster.yandex.com/tools/server-response/) the correctness of the server response to the indexing bot. If there are no errors, the information in Yandex Webmaster will be updated within a few days.
||
||
The domain name was not renewed on time.
|
Renew the domain registration. After this, the error message in Yandex Webmaster will disappear within a few days.
||
|#
## The site is closed for indexing in the robots.txt file {#set-robots}
Several times a day, the indexing bot requests the [robots.txt](https://yandex.com/support/webmaster/en/controlling-robot/robots-txt.md) file and updates information about it in its database. If the robot receives a disallow directive as a response, the information about the site and its page content won't be updated.
**How to fix**
Troubleshooting depends on the error:
#|
|| **Reason** | **Solution** ||
||
The bot received a disallow directive.
|
[Check](https://webmaster.yandex.com/tools/robotstxt/) the contents of the `robots.txt` file:
- If crawling is blocked, unblock it.
- If you can't remove the block yourself, contact your hosting provider or domain name registrar.
Once the error is fixed, the information in Yandex Webmaster will be updated within a few days.
||
||
The domain name was not renewed on time.
|
The `robots.txt` file contains disallow directives for the bot. Renew the domain registration. After this, the error message in Yandex Webmaster will disappear within a few days.
||
||
The site is available over HTTP and HTTPS, but the protocol specified in Yandex Webmaster is HTTP.
|
The `robots.txt` file prohibits both versions of the site (HTTP and HTTPS). Because of that, the site isn't indexed in search results.
To make the HTTPS site appear in search results:
1. Add the HTTPS version of your site to Yandex Webmaster.
1. [Set up redirection](https://yandex.com/support/webmaster/en/yandex-indexing/https-migration.md#redir) from HTTP to the HTTPS version.
1. Open Yandex Webmaster and [submit a site migration request](https://yandex.com/support/webmaster/en/yandex-indexing/https-migration.md#other).
During the next visit, the indexing bot will see the changes, and the error message in Yandex Webmaster will disappear.
||
|#
## Security problems or violations detected {#threats}
**How to fix**
1. See the description of the violation and recommendations for correcting it.
{% cut "List of possible violations" %}
- [SEO texts](https://yandex.com/support/webmaster/en/threat/seo-text.md)
- [Unexpected redirection](https://yandex.com/support/webmaster/en/threat/unexpected-redirection.md)
- [Mimicry](https://yandex.com/support/webmaster/en/threat/mimicry.md)
- [Cloaking](https://yandex.com/support/webmaster/en/threat/cloaking.md)
- [Unwanted software](https://yandex.com/support/webmaster/en/threat/undesirable.md)
- [Social engineering and deception](https://yandex.com/support/webmaster/en/threat/social-engineering.md)
- [Fraudulent actions](https://yandex.com/support/webmaster/en/threat/unfair-actions.md)
- [Low-value content](https://yandex.com/support/webmaster/en/threat/useless-content.md)
- [User behavior simulator](https://yandex.com/support/webmaster/en/threat/user-actions-imitation.md)
{% endcut %}
1. Fix the violation and submit the site for reindexing.
Learn more:
* [Site security and violations](https://yandex.com/support/webmaster/en/service/security-threats.md)
## Slow server response {#request}
When the indexing bot crawls your site, it records the average server response time on its pages. If some pages take more than three seconds to load, the bot records this as an error. If the server is slow, indexing may be delayed.
The list of pages is displayed in the error message.
**How to fix**
Check the [server response](https://yandex.com/support/webmaster/en/indexing-options/server-response.md) time.
If the server response is fast when you check it, ignore the error message. The message will disappear the next time the indexing bot crawls your site.
On how to speed up page reindexing by the bot, see [How can I add a site to search?](https://yandex.com/support/webmaster/en/robot-workings/robot.md).
## Invalid SSL certificate settings {#ssl}
An SSL certificate is a digital certificate that provides a secure encrypted connection between a site and a browser using the SSL protocol. The certificate contains information about the domain owner, its validity period, the name of the certification authority, and the public key needed for encryption.
If a site has an SSL certificate, it is indicated in the browser’s address bar with the `https` prefix or an icon. For example, Yandex Browser uses this icon .
An SSL certificate configuration error occurs in the following cases:
- The certificate has expired.
- The certificate was issued for a different domain or not for all subdomains where it is used. For example, the certificate was issued for the domain `example.com` but is used for the domain `www.example.com`.
- The certificate from the certification authority is missing in users' browsers or it has been revoked.
- A self-signed certificate is used.
If there is an SSL certificate configuration error on the site, the browser will show a warning. Typically, users avoid such sites.
**How to fix**
To fix the error, check the SSL certificate and the server settings. To do this, contact your hosting provider.
The next the time the indexing bot crawls your site, it'll see the changes, and — if there is no error — the error message will disappear in Yandex Webmaster.
## Duplicate pages with GET parameters were found {#get-params}
There are duplicate pages on the site with the same content, but the URLs for these pages are different. When crawling your site, the indexing bot records duplicate pages separately from each other or may group them together.
Some links with GET parameters in the URL duplicate the content of pages without GET parameters. For example, `https://example.com/tovary?from=mainpage` duplicates `https://example.com/tovary`.
If your website has duplicate pages:
- The page you need may disappear from search results.
When crawling your site, the indexing bot may select another page from the group of duplicates.
Sometimes, duplicate pages are not grouped and appear in search results as different documents. Such pages will compete with each other, which will negatively affect your site’s rank in search results.
- The site's address may change depending on which page remains in search results. This makes it difficult to view site statistics in web analytics services.
- The robot may take longer to re-crawl your site. As a result, information about the pages that are important to you is sent to the search engine database more slowly, and the bot creates an additional load on the website.
**How to fix**
To remove duplicates and let the bot know which page should be included in the search, add the [Clean-param](https://yandex.com/support/webmaster/en/robot-workings/clean-param.md) directive to `robots.txt`. The robot won't take into account the parameters in the URL.
Once the error is fixed, the data will be updated within a few days, and the message in Yandex Webmaster will disappear.
{% note tip %}
Clean-param is an intersectional directive, meaning it can be placed anywhere in the `robots.txt` file. If you add other directives for the Yandex's indexing bot, list them in one section. In this case, the `User-agent: *` string won't be taken into account for Yandex.
{% endnote %}
{% cut "Example of the Clean-param directive" %}
```no-highlight
#for URLs like:
https://example.com/page?utm_source=link&utm_medium=cpc&utm_campaign=new
#robots.txt will contain:
User-agent: Yandex
Clean-param: utm_source&utm_medium&utm_campaign /page
#this way we indicate that the URL that needs to remain in search results should be https://example.com/page
#for the directive to apply to pages at any URL, don't specify the URL:
User-agent: Yandex
Clean-param: utm_source&utm_medium&utm_campaign
```
{% endcut %}
{% cut "Contact support" %}
Tell us what your question is about so we can direct you to the right specialist:
{% list tabs radio %}
- Failed to connect to the server due to DNS error
If you followed [the recommendations](#dns-error) and the site is available for the robot, but the error still appears in Yandex Webmaster, fill out the form:
- The site is closed for indexing in the robots.txt file
If you followed the [recommendations](#set-robots), but the error still appears in Yandex Webmaster, fill out the form:
- Invalid SSL certificate settings
If you followed the [recommendations](#ssl), but the error still appears in Yandex Webmaster, fill out the form:
- Duplicate pages with GET parameters were found
If you recently added [Clean-param](https://yandex.com/support/webmaster/en/robot-workings/clean-param.md) directives, prohibited crawling duplicates using [robots.txt](https://yandex.com/support/webmaster/en/controlling-robot/robots-txt.md), or placed the [rel="canonical"](https://yandex.com/support/webmaster/en/robot-workings/canonical.md#set-canonical) attribute, it may take a few days for these changes to be reflected in **Site diagnostics** in Yandex Webmaster and for the notification to stop displaying.
If the error still appears in Yandex Webmaster after a while, fill out the form:
- Other problems
{% endlist %}
{% endcut %}
[*DNS]: A service that converts readable site names (for example, `example.ru`) into their numeric IP addresses. The server stores information about domains and knows which IP address corresponds to which site.