Cannot query data in SharePoint using Rest Api

Question

I have been using this in-4-steps-access-sharepoint-online-data-using-postman-tool article for some time to get access token to get data from SharePoint. It worked fine. However, now I have client where I try to do the same and I am getting following exception, when I try run Rest Api. Access Token was sent to me correctly. Is there anything else I might missing for this client?

{
    "error": {
        "code": "-2147024891, System.UnauthorizedAccessException",
        "message": {
            "lang": "en-US",
            "value": "Access denied. You do not have permission to perform this action or access this resource."
        }
    }
}

Answer 1

Hi PavelBrokhman-0975,

I am able to reproduce this issue.

After go through the blog again i find that there is a mistake:

The permission should be :

<AppPermissionRequests AllowAppOnlyPolicy="true">  
<AppPermissionRequest Scope="http://sharepoint/content/sitecollection/web" Right="FullControl" />  
</AppPermissionRequests>  

After I grant the permissions again, it works well!

So can you grant permissions again to see if it works? Also you may have a look this blog.

Best Regards,
Baker Kong

Answer 2

I did see this issue with the missing tag and when I added the trusted application I have put it in before creation.

Also, I have reviewed this blog as well and tenant configuration set to Allow for both options mentioned in the blog.