Incoming webhook

06/18/2025

Important

The existing Microsoft 365 (previously called Office 365) connectors across all cloud platforms are nearing deprecation, and the creation of new Microsoft 365 connectors will soon be blocked. For more information on the schedule and how the Workflows app provides a more flexible and secure experience, see retirement of Microsoft 365 connectors within Microsoft Teams.

This sample demonstrates a Teams tab where users can input Incoming Webhook URLs and send message cards to a specified Teams channel, illustrating the HttpPOST action for interactive message cards. It includes setup steps for running the sample, testing in multiple environments such as Outlook and Office, and provides insights into webhooks and connectors for extending Microsoft 365 apps.

Included Features

Tabs
Incoming Webhooks

Interaction with tab

webhook-tab

Prerequisites

.NET Core SDK version 6.0

# determine dotnet version
dotnet --version

Publicly addressable https url or tunnel such as dev tunnel or ngrok latest version or Tunnel Relay
Teams Microsoft Teams is installed and you have an account
Microsoft 365 Agents Toolkit for Visual Studio

Run the app (Using Microsoft 365 Agents Toolkit for Visual Studio)

The simplest way to run this sample in Teams is to use Microsoft 365 Agents Toolkit for Visual Studio.

Install Visual Studio 2022 Version 17.14 or higher Visual Studio
Install Microsoft 365 Agents Toolkit for Visual Studio Microsoft 365 Agents Toolkit extension
In the debug dropdown menu of Visual Studio, select Dev Tunnels > Create A Tunnel (set authentication type to Public) or select an existing public dev tunnel.
In the debug dropdown menu of Visual Studio, select default startup project > Microsoft Teams (browser)
Right-click the 'M365Agent' project in Solution Explorer and select Microsoft 365 Agents Toolkit > Select Microsoft 365 Account
Sign in to Microsoft 365 Agents Toolkit with a Microsoft 365 work or school account
Set Startup Item as Microsoft Teams (browser).
Press F5, or select Debug > Start Debugging menu in Visual Studio to start your app
In the opened web browser, select Add button to install the app in Teams

If you do not have permission to upload custom apps (uploading), Microsoft 365 Agents Toolkit will recommend creating and using a Microsoft 365 Developer Program account - a free program to get your own dev environment sandbox that includes Teams.

Setup

1. Setup for incoming webhook

Create a incoming webhook. Create incoming webhooks. Keep this webhook URL handy while running the sample.

2. Setup NGROK

Run ngrok - point to port 3978
```
ngrok http 3978 --host-header="localhost:3978"
```
Alternatively, you can also use the dev tunnels. Please follow Create and host a dev tunnel and host the tunnel with anonymous user access command as shown below:
```
devtunnel host -p 3978 --allow-anonymous
```

3. Setup for code

Clone the repository

git clone https://github.com/OfficeDev/Microsoft-Teams-Samples.git

In a terminal, navigate to samples/incoming-webhook/csharp/ClientApp
```
npm install
```
If you face any dependency error while installing node modules, try using below command
```
npm install --legacy-peer-deps
```
In a terminal, navigate to samples/incoming-webhook/csharp
```
# change into project folder
cd # IncomingWebhook
```
Run the app from a terminal or from Visual Studio, choose option A or B.

A) From a terminal

# run the app
dotnet run

B) Or from Visual Studio

Launch Visual Studio
File -> Open -> Project/Solution
Navigate to IncomingWebhook folder
Select IncomingWebhook.csproj file
Press F5 to run the project

4. Setup Manifest for Teams

This step is specific to Teams.
- Edit the manifest.json contained in the appPackage folder to replace {{Manifest-id}} with any GUID ID.
- Edit the manifest.json for contentUrl, websiteUrl inside staticTabs section. Replace <<Domain-name>> with app's base Url domain. E.g. if you are using ngrok it would be https://1234.ngrok-free.app then your domain-name will be 1234.ngrok-free.app and if you are using dev tunnels then your domain will be like: 12345.devtunnels.ms.
- Note: If you want to test your app across multi hub like: Outlook/Office.com, please update the manifest.json in the incoming-webhook\csharp\IncomingWebhook\Manifest_Hub folder with the required values.
- Zip up the contents of the appPackage folder to create a Manifest.zip or Manifest_Hub folder to create a Manifest_Hub.zip(Make sure that zip file does not contains any subfolder otherwise you will get error while uploading your .zip package)
- Upload the manifest.zip to Teams (In Teams Apps/Manage your apps click "Upload an app". Browse to and Open the .zip file. At the next dialog, click the Add button.)
- Add the app to personal scope.