> Source: [sk182129](https://support.checkpoint.com/results/sk/sk182129)

# sk182129 - Site fails to load with "ERR_CERT_INVALID" error after importing a custom certificate to HTTPS Inspection

| Property | Value |
|----------|-------|
| Solution ID | sk182129 |
| Date Created | 2024-04-29 |
| Last Modified | 2025-05-16 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82, R81.20, R81.10 (EOS), R81 (EOS) |

## Symptoms

- * Browser shows error: `"NET::ERR_CERT_INVALID"` and fails to load site after adding a custom certificate to HTTPS Inspection blade.

* The error details:

  `
  [website] uses encryption to protect your information. When [browser] tried to connect to [website] this time, the website sent back unusual and incorrect credentials.
  You can't visit [website] right now because the website sent scrambled credentials that [browser] can't process. Network errors and attacks are usually temporary, so this page will probably work later.`

* If you turn off the HTTPS Inspection blade or use the default/auto-generated certificate, 
  the issue does not occur.

## Cause

The custom certificate that was imported to the HTTPS Inspection blade is not a CA certificate.

Open the certificate in the browser, go to **Details** and click **Certificate Basic Constraints** to see if this is a CA certificate.

* Example of Server certificate (incorrect)

  ![](https://sc1.checkpoint.com/sc/SolutionsStatics/NEW_SK_NOID1710966253654/server-certificate202403201529501.png)
* Example of CA certificate (correct)

  ![](https://sc1.checkpoint.com/sc/SolutionsStatics/NEW_SK_NOID1710966253654/ca-certificate202403201530332.png)

## Solution

This solution requires authentication. Please log in to view the full solution.

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