Hi @Ward Horsfall ,
Using Graph API you can first create a draft message with category property.
Please find the below c# code for the same:
GraphServiceClient graphClient = new GraphServiceClient( authProvider );
var message = new Message
{
Subject = "Did you see last ",
Importance = Importance.Low,
Categories = new List<String>()
{
"Blue category"
},
Body = new ItemBody
{
ContentType = BodyType.Html,
Content = "They were <b>awesome</b>!"
},
ToRecipients = new List<Recipient>()
{
new Recipient
{
EmailAddress = new EmailAddress
{
Address = "test1@raiinfy.onmicrosoft.com"
}
}
}
};
await graphClient.Me.Messages
.Request()
.AddAsync(message);
It will create a draft message with category as shown below
Then you have to send mail using the message id created in the above step.
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