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BrandonLau-1431 asked SharonZhao-MSFT commented

Importing third-party messages to Teams - GCCH

Hello, we're in the process of transitioning to Microsoft 365. Currently I'm tasked with importing messages from our on-site Mattermost chat service.
I'm working with the Graph API to programmatically import the Teams, Channels, and messages into Teams.

Using the beta API:

It errors out with the explanation that API is not supported in GCCH.

I'm just wondering if anyone has any suggestions or has run into a similar situation. I'm just looking for the best way to complete this task.

Thank you!

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SharonZhao-MSFT answered SharonZhao-MSFT commented


I have no access to your link. So, I cannot see the real content.

Before this progress, please note that this release is not intended for use in production.

GCC-High doesn’t support for developing for Microsoft Teams. If you are a Microsoft 365 subscriber, you can develop apps for Microsoft Teams with one of the following plans:

  • Basic

  • Standard

  • Enterprise E1, E3, and E5

  • Developer

  • Education, Education Plus, and Education E5

For importing third-party platform messages to Teams, you must meet the necessary requirements:
Analyze and prepare message data

✔ Review the third-party data to decide what will be migrated.

✔ Extract the selected data from the third-party chat system.

✔ Map the third-party chat structure to the Teams structure.

✔ Convert import data into format needed for migration.

Set up your Office 365 tenant

✔ Ensure that an Office 365 tenant exists for the import data. For more information on setting up an Office 365 tenancy for Teams, see, Prepare your Office 365 tenant.

✔ Make sure that team members are in Azure Active Directory (AAD). For more information see Add a new user to Azure Active Directory.

About program question, it is not in our scope. I will add office-teams-app-dev tag to get further help on this side. Thanks for your understanding.

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1 Vote 1 ·

Your idea seems to makes sense. But no official document explains how to do that.
You could have a test if possible.

1 Vote 1 ·

Hi Sharon,
Thanks for the message.

Is it possible to import the third-party messages into a non GCC High environment -> Export the teams data -> Import to GCC High?


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If you have any update of this thread, please feel free to share with us here.
Have a nice day!

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Haven't received your update for a long time, if you have any update on this topic, please feel free to drop us a note.
Thanks for your understanding.

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