This field contains duplicate values. Remove all duplicate values and try the operation again. ErrorCode: -2130246237
説明
When performing a Copy/Paste from the Navigator (SharePoint Online to SharePoint Online) via CSOM you get the following error: "This field contains duplicate values. Remove all duplicate values and try the operation again. ErrorCode: -2130246237"
対策
To migrate SharePoint Online sites use Hyper Migration, Drives > Copy SharePoint Online to SharePoint Online