Hello Kaustubh Nangare,
I successfully retrieved all SharePoint sites using the endpoint "https://graph.microsoft.com/v1.0/sites" with the Application permission Sites.Read.All. The delegated permission is not supported for this request, as noted in the documentation provided.
https://learn.microsoft.com/en-us/graph/api/site-get?view=graph-rest-1.0&tabs=http#permissions
- Using Application permission to list Sites
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