Troubleshooting
Enabling Custom App Uploads in Microsoft Teams
Your Teams tenant administrator needs to update a few settings in the Teams Admin Center to allow uploading custom apps (via .zip).
1. Allow custom apps org-wide
Go to Teams apps → Manage apps
Click Actions dropdown then Org-wide app settings
Ensure "Let users interact with custom apps" is toggled On
Ensure "Let users install and use available apps" is toggled On
Ensure "Third-party apps" is toggled On
Click Save
2. Enable "Upload custom apps" in the setup policy
Go to Teams apps → Setup policies
Click on Global (Org-wide default) (or create a new policy if you only want to allow specific users — see note below)
Toggle "Upload custom apps" to On
Click Save
If using a custom policy, assign it to the relevant users via Manage users
3. Check app permission policies
Go to Teams apps → Permission policies
Select the relevant policy (e.g. Global)
Under Third-party apps and Custom apps, ensure apps are set to Allow all apps (or that the specific app is explicitly allowed)
Click Save
Restricting uploads to specific users only
If you don't want all users in your organization to be able to upload custom apps, you can scope it to specific people instead of editing the Global policy:
Go to Teams apps → Setup policies
Click Add to create a new policy
Give it a name and description (e.g. "Custom app uploaders")
Toggle "Upload custom apps" to On
Click Save
Select the new policy, click Manage users, and add the specific users who should be allowed to upload
Leave the Global (Org-wide default) policy with "Upload custom apps" toggled Off
Only users assigned to this custom policy will be able to upload apps.
Important notes
Changes can take up to 24 hours to take effect.
After setup, users can upload the app via Apps → Manage your apps → Upload an app → Upload a custom app.