# Invalid redirect: http://localhost:3000/api/zoom/callback (4,700)

**URL:** <https://devforum.zoom.us/t/invalid-redirect-http-localhost-3000-api-zoom-callback-4-700/144664>\
**Category:** Authentication\
**Tags:** api\
**Created:** [July 9, 2026, 2:45am UTC](https://devforum.zoom.us/t/invalid-redirect-http-localhost-3000-api-zoom-callback-4-700/144664 "2026-07-09T02:45:10Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Srinip](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@Srinip](https://devforum.zoom.us/u/Srinip)\
**Post date:** [July 9, 2026, 2:45am UTC](https://devforum.zoom.us/t/invalid-redirect-http-localhost-3000-api-zoom-callback-4-700/144664/1 "2026-07-09T02:45:10Z")

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I have created a **general app (General app 600)** and completed the steps and made it localready.

I have generated the below URL, which should take me to the login screen so that the user can authorize the app and receive the access token and the refresh token.

Below is the URL

[https://zoom.us/oauth/authorize?response\_type=code&client\_id=WYzSPWOOT2eakawUm3AWw&redirect\_uri=http://localhost:3000/api/zoom/callback](https://zoom.us/oauth/authorize?response_type=code&client_id=WYzSPWOOT2eakawUm3AWw&redirect_uri=http://localhost:3000/api/zoom/callback)

It was working fine until last week but since Monday, it is not redirecting to the login screen and is returning the following error:

```auto
{"status":false,"errorCode":4700,"errorMessage":"Invalid redirect url","result":null}

```

Please resolve this urgently.We are waiting for this.

Thanks & Regards

Srinivas Polishetty

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**Author:** ![freelancer.nak](https://sea2.discourse-cdn.com/flex016/user_avatar/devforum.zoom.us/freelancer.nak/32/40968_2.png) [@freelancer.nak](https://devforum.zoom.us/u/freelancer.nak)\
**Post date:** [July 9, 2026, 2:50am UTC](https://devforum.zoom.us/t/invalid-redirect-http-localhost-3000-api-zoom-callback-4-700/144664/2 "2026-07-09T02:50:57Z")

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@Srinip Hi,

> [@Error 4700 Invalid Redirect on every new OAuth app](https://devforum.zoom.us/t/error-4700-invalid-redirect-on-every-new-oauth-app/144596/3):
>
> @LenCole Hi, As already mentioned by @chunsiong.zoom, localhost isn’t supported for redirect URLs - you either use your staging/development environment’s redirect URL (the simplest option if you already have one deployed), or create a local domain via /etc/hosts (or the Windows hosts file), e.g. yourdomain.dev, pointed at whatever port your app runs on locally. I’m sharing my whole nginx config above just for reference, but you really only need a simple sample. Below is a minimal example using…

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**Author:** ![Patrick12](https://sea2.discourse-cdn.com/flex016/user_avatar/devforum.zoom.us/patrick12/32/76076_2.png) [@Patrick12](https://devforum.zoom.us/u/Patrick12)\
**Post date:** [August 18, 2026, 3:47am UTC](https://devforum.zoom.us/t/invalid-redirect-http-localhost-3000-api-zoom-callback-4-700/144664/3 "2026-08-18T03:47:34Z")

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Same 4700 here as of August 2026, still broken.

We’re connecting Cursor / Grok Bot to Zoom’s official MCP using a user-managed General app on a business Zoom account. Cursor sends:

`redirect_uri=http://localhost:8787/callback`

That exact URL is in both the OAuth Redirect URL field and the OAuth Allow List (Development). We also allowlisted `https://localhost:8787/callback` and `https://www.cursor.com/agents/mcp/oauth/callback`. Scopes are added. Strict Mode is off.

Authorize still returns:

`{"status":false,"errorCode":4700,"errorMessage":"Invalid redirect url","result":null}`

This matches the reports that Zoom stopped accepting localhost redirects. Cursor’s MCP desktop/agent flow hardcodes localhost:8787, so we cannot complete Zoom MCP OAuth at all.

Can Zoom confirm whether localhost / loopback redirects are intentionally blocked now, and if there’s a supported path for local MCP clients that must use `http://localhost:8787/callback`?

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<div class="post-metadata">

**Author:** ![expertswho](https://sea2.discourse-cdn.com/flex016/user_avatar/devforum.zoom.us/expertswho/32/60945_2.png) [@expertswho](https://devforum.zoom.us/u/expertswho)\
**Post date:** [August 19, 2026, 6:48am UTC](https://devforum.zoom.us/t/invalid-redirect-http-localhost-3000-api-zoom-callback-4-700/144664/4 "2026-08-19T06:48:34Z")

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hi @Srinip , @Patrick12

You cannot do OAuth or **callback** to Zoom from localhost.

When you use Zoom for any kind of authentication, Zoom needs an external URL to connect to.

If you are testing, then you can use a tool like ngrok to tunnel an external URL.  
When you roll out on a server, I expect you will then have an external URL.

This is because the auth goes to Zoom, who will show a page from Marketplace to get approval, and then they need a registered return URL for the Marketplace to connect to.  
An external Marketplace App can not connect to your local URL; it is the Marketplace that is trying to connect, not the browser.

I hope that makes things clear.

John