> Source: [sk169573](https://support.checkpoint.com/results/sk/sk169573)

# sk169573 - "500 Internal Server Error" occurs while accessing one website through Check Point Proxy

| Property | Value |
|----------|-------|
| Solution ID | sk169573 |
| Date Created | 2020-10-13 |
| Last Modified | 2020-10-14 |
| Technical Level | General |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |

## Symptoms

- * "`500 Internal Server Error`" appears when the user opens a website. The user cannot access the resource hosted on this website.   
  **Note**: The Check Point Security Gateway acts as a HTTP/HTTPS Proxy.
* X-Forwarded-For header is enabled under HTTP/HTTPS Proxy Settings, but the procedure in [sk100223](https://supportcenter.checkpoint.com/supportcenter/portal?eventSubmit_doGoviewsolutiondetails=&solutionid=sk100223) (to strip X-Forward-For HTTP header) does not change the behavior.

  <br />

## Cause

This is an issue on the web server side. The web server cannot handle the HTTP request with the X-Forwarded-For (XFF) header and returns the "`500 Internal Server Error`" if it sees the XFF header.

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## Solution

Normally, the X-Forwarded-For header could be stripped on the network device. If the X-Forwarded-For header added by the Check Point Security Gateway is not needed for third-party network devices (i.e., Internet firewall) deployed in the user's environment to identify the actual source IP of PC clients behind the proxy, it is possible to disable this feature on the Check Point Security Gateway as follows.  

1. Edit the Security Gateway object in SmartConsole.  

2. Uncheck **X-Forward-For header (original client source IP address)** under **HTTP/HTTPS Proxy** \> **Advanced** :  

![](https://sc1.checkpoint.com/sc/SolutionsStatics/sk169573/sk169573202009231429321.png)  

3. Save the changes and install the policy.

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