How to get user's information from Active Directory by email address using Microsoft Graph sdk

问题

We would like to retrieve user's information from Azure Active directory using Microsoft Graph SDK.

Given a valid email address, but I get an error

Resource 'myemailaddress@live.com' does not exist or one of its queried reference-property objects are not present.

Code is below. Can you please guide?

IConfidentialClientApplication confidentialClientApplication = ConfidentialClientApplicationBuilder.Create(clientId).WithTenantId(tenantID).WithClientSecret(clientSecret).Build();
ClientCredentialProvider authProvider = new ClientCredentialProvider(confidentialClientApplication);
GraphServiceClient graphClient = new GraphServiceClient(authProvider);
var user = await graphClient.Users["myemailaddress@live.com"].Request().GetAsync();

回答1:

I can reproduce your issue. The account myemailaddress@live.com is a Guest in your tenant, navigate to the AAD in the portal -> find the account -> click it and fetch the Object ID, then use the Object ID in the code, it will work.

var user = await graphClient.Users["<Object ID>"].Request().GetAsync();

Or you can use filter to get the user, in your case, the format of the UserPrincipalName for the guest user will be like myemailaddress_live.com#EXT#@tenantname.onmicrosoft.com, when using the filter, we need URL encode it, then it will be myemailaddress_live.com%23EXT%23%40tenantname.onmicrosoft.com, try the code as below, it works on my side.

var user = await graphClient.Users.Request().Filter("UserPrincipalName eq 'myemailaddress_live.com%23EXT%23%40tenantname.onmicrosoft.com'").GetAsync();

Update:

If you want to get the user via UserPrincipalName, you can also use the url encoded one as below.

var user = await graphClient.Users["myemailaddress_live.com%23EXT%23%40tenantname.onmicrosoft.com"].Request().GetAsync();

来源：https://stackoverflow.com/questions/58222315/how-to-get-users-information-from-active-directory-by-email-address-using-micro