> Source: [sk154932](https://support.checkpoint.com/results/sk/sk154932)

# sk154932 - Cannot access the Outlook Web Access (OWA) application, browser tries to resolve a different address 

| Property | Value |
|----------|-------|
| Solution ID | sk154932 |
| Date Created | 2019-05-30 |
| Last Modified | 2020-05-11 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |

## Symptoms

- When the user tries to access the OWA application, the browser fails to reach the site. The address bar shows that the browser tries to resolve a different address than what was entered by the user.

## Cause

The request Host header value shows the Security Gateway's Reverse Proxy host-name.

You can see the Host header by using Fiddler.

### Example

GET https://owa.mydomain.com/owa HTTP/1.1

**Host: owa.mydomain.com**

By default, the Host header is "thrown" from the request in order to be as "clean" as possible and not intervene in any translation. Throwing the Host header ensures that the Security Gateway instead forwards the internal host-name as it is configured in the Reverse Proxy policy.

However, when the correct header is forwarded to the internal host, it is also echoed back "as is" in subsequent "Location:"headers (of 301/302 responses). In the address bar, you would see the redirection from the internal server.

The reply from the internal host may look as below:

` `

`HTTP/1.1 302 Found`

` `

`Date: Thu, 30 May 2019 14:55:49 GMT`

` `

`Server: CPWS`

` `

`Content-Length: 225`

` `

**Location:**`https://internal_hostname/owa/auth/logon.aspx?url=https%3a%2f%2fexch-aws.mydomain.com%2fowa&reason=0`

**Note**: The location in the above example is not an address the user can resolve from an external network, and the browser would fail to resolve the site name.

## Solution

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