# I can't authenticate my application

**URL:** <https://devforum.zoom.us/t/i-cant-authenticate-my-application/83108>\
**Category:** Authentication\
**Created:** [February 14, 2023, 12:37pm UTC](https://devforum.zoom.us/t/i-cant-authenticate-my-application/83108 "2023-02-14T12:37:05Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![a.s.rwar](https://sea2.discourse-cdn.com/flex016/user_avatar/devforum.zoom.us/a.s.rwar/32/45474_2.png) [@a.s.rwar](https://devforum.zoom.us/u/a.s.rwar)\
**Post date:** [February 14, 2023, 12:37pm UTC](https://devforum.zoom.us/t/i-cant-authenticate-my-application/83108/1 "2023-02-14T12:37:05Z")

</div>

```auto
<?php
require_once 'config.php';
  
try {
    $client = new GuzzleHttp\Client(['base_uri' => 'https://zoom.us']);
  
    $response = $client->request('POST', '/oauth/token', [
        "headers" => [
            "Authorization" => " Basic ZjZXdDB0SFpTUlN3MGxPV0twRFlROlZBNnpqTTJoSjFjQUs0MDZUTnB5blA2NUU1dTExZXJJ"
        ],
        'form_params' => [
            "grant_type" => "authorization_code",
            "code" => $_GET['code'],
            "redirect_uri" => REDIRECT_URI
        ],
    ]);
  
    $token = json_decode($response->getBody()->getContents(), true);
  
    $db = new DB();
    $db->update_access_token(json_encode($token));
    echo "Access token inserted successfully.";
} catch(Exception $e) {
    echo $e->getMessage();
}

```

```
this is my callback, it looks all right but it makes me this error:

```

Client error: `POST https://zoom.us/oauth/token` resulted in a `400 Bad Request` response: {“reason”:“Bad Request”,“error”:“invalid\_request”}

---

<div class="post-metadata">

**Author:** ![elisa.zoom](https://sea2.discourse-cdn.com/flex016/user_avatar/devforum.zoom.us/elisa.zoom/32/47836_2.png) [@elisa.zoom](https://devforum.zoom.us/u/elisa.zoom)\
**Post date:** [February 21, 2023, 6:11pm UTC](https://devforum.zoom.us/t/i-cant-authenticate-my-application/83108/2 "2023-02-21T18:11:17Z")

</div>

Hey @a.s.rwar  
Thanks for reaching out to the Zoom Developer Forum.  
Were you able to troubleshoot this issue?

---

<div class="post-metadata">

**Author:** ![geoff.crego](https://avatars.discourse-cdn.com/v4/letter/g/53a042/32.png) [@geoff.crego](https://devforum.zoom.us/u/geoff.crego)\
**Post date:** [August 31, 2023, 3:23pm UTC](https://devforum.zoom.us/t/i-cant-authenticate-my-application/83108/3 "2023-08-31T15:23:34Z")

</div>

Did you ever get past this issue? If so how?

---

<div class="post-metadata">

**Author:** ![elisa.zoom](https://sea2.discourse-cdn.com/flex016/user_avatar/devforum.zoom.us/elisa.zoom/32/47836_2.png) [@elisa.zoom](https://devforum.zoom.us/u/elisa.zoom)\
**Post date:** [September 6, 2023, 2:15pm UTC](https://devforum.zoom.us/t/i-cant-authenticate-my-application/83108/4 "2023-09-06T14:15:07Z")

</div>

Hi @geoff.crego  
It looks like we did not get a response here.  
Are you experiencing this on your end?