Set up your dev environment for extending Teams apps across Microsoft 365
The development environment for extending Teams apps across Microsoft 365 is similar to Microsoft Teams development. This article discusses specific configurations required to run preview builds of Microsoft Teams and Microsoft 365 applications in order to preview Teams apps running in Outlook and Microsoft 365 app.
To set up your development environment:
Prepare a Developer Tenant for testing
You need a Microsoft 365 developer subscription sandbox tenant to set up your dev environment. If you don't already have one, create a sandbox tenant or get a test tenant through your organization.
As you set up for testing, ensure that you sign out of all other accounts and sign in with the account you intend to use for testing.
You also need to enable sideloading for your tenant:
Sign in to Teams admin center with your test tenant credentials.
Go to Teams apps > Manage apps.
At the top right, select Org-wide app settings.
Under Custom apps, turn on the Interaction with custom apps toggle and Save.
Apart from Org-wide app settings, custom app policy settings also allow users to upload custom apps to Teams. For more information, see manage custom app policies and settings.
In the Teams admin center, go to Teams apps > Setup policies, and then select Global (Org-wide default) policy.
Turn on Upload custom apps, and select Save.
Enroll your developer tenant for Microsoft 365 Targeted Releases
It can take up to five days after creating a Microsoft 365 developer sandbox tenant and enrolling in Microsoft 365 Targeted Releases for sideloaded Teams apps to appear in Outlook and Microsoft 365 app.
To enroll your test tenant for Microsoft 365 Targeted Releases:
Sign in to Microsoft 365 admin center with your test tenant credentials.
Go to Settings > Org Settings > Organization profile.
Select Release preferences.
Select any Targeted Release preference:
- Targeted Release for everyone
- Targeted Release for select users
For more information on Microsoft 365 release options, see set up the Standard or Targeted Release options in Microsoft 365 admin center help.
Install Microsoft 365 apps in your test environment
You can preview Teams apps running in Outlook on Windows desktop by using a recent Beta Channel build. Check if you have to change the Microsoft 365 Apps update channel for your test tenant to install a Microsoft 365 Beta Channel build.
To install Microsoft 365 Beta Channel applications in your test environment:
Sign in to your test environment with your test tenant credentials.
Download and run the Office Deployment Tool.
Select a local folder to store the extracted files.
Go to the local folder and open configuration-Office365-x86.xml (or *x64.xml, depending on your environment) in a text editor and update the Channel value to
Open Command Prompt and go to the local folder path.
setup.exe /configure configuration-Office365-x86.xml(or use the *x64.xml file, depending on your setup).
Open Outlook (desktop client) and set up the mail account using your test tenant credentials.
Open File > Office Account > About Outlook to confirm you're running a Microsoft 365 Beta Channel build of Outlook.
Verify that Microsoft Edge WebView2 Runtime is installed. Open Windows Start > Apps & features, and search for webview:
If it's not listed, install Microsoft Edge WebView2 to your test environment.
You can preview Teams personal tabs running in Microsoft 365 app for Android by joining the beta program.
To install the latest Microsoft 365 app beta, build to your physical Android device or Android emulator:
Ensure you use a Google Play supported Android device.
Launch the Play Store on your Android device.
Search for "Office" and select Office (Microsoft 365).
Select the Install button.
Select Join under Join the beta section after the installation completes.
Launch the Microsoft 365 app and sign in with your test tenant credentials.
Open your profile (Me) > Settings and scroll to the bottom of the menu.
Ensure you use Microsoft 365 app version 16.0.15726.20000 or higher for Android.
Install Visual Studio Code and Teams Toolkit extension
Optionally, you can use Visual Studio Code to extend Teams apps into Microsoft 365 and Outlook.
The extension Teams Toolkit for Visual Studio Code (
v2.10.0 or later) provides commands that can help modify your existing Teams code to be compatible with Outlook and Microsoft 365. For more information, see enable Teams personal tab for Microsoft 365 and Outlook.
Create or update a Teams app to run across Microsoft 365: