MSGraphClient and this SDK should not be mutually convertible. This SDK encapsulates the API inside the method and only needs to provide parameters. If you want to use MSGraphClient, you can use this API:Upload large files with an upload session
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Hi @johnjohn-0472 ,
If my reply helps you, please mark the reply as the answer, it will make others who stuck with a similar issue easier to search for valid solutions in this forum.

Please share the code for further research.

Could you share the script you are using?

I just download the code of the blog from Github. Then made some small changes to adapt to my environment.
You could get it here:https://github.com/Amos-MSFT/SharePoint-FrameWork-Demos/tree/master/SPFxAngular9-master

Hi @msdc,
I am checking to see how things are going there on this issue. Please let us know if you would like further assistance.
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Hi @Mikello-6626 ,
Do you have any update on this issue?

You're welcome :）.

I am checking to see how things are going there on this issue. Please let us know if you would like further assistance.
You can accept the helpful post as the answer to help other community members find helpful information quickly.

I am checking to see how things are going there on this issue. Please let us know if you would like further assistance.
You can accept the helpful post as the answer to help other community members find helpful information quickly.

I am checking to see how things are going there on this issue. Please let us know if you would like further assistance.
You can accept the helpful post as the answer to help other community members find helpful information quickly.

You're welcome.

I use the postman to get the access token.

https://login.microsoftonline.com/`YourTenantName`.onmicrosoft.com/oauth2/token
grant_type:client_credentials

client_id:Your Portal Application ID

client_secret:Your application Key

resource:https://graph.microsoft.com/

SharePoint 2016 use .NET Framework 4.6, so both versions should be ok.

After the comments column has been updated, new emails can be sent to include new comments, but old emails cannot be synchronized to the new comments.