question

Hi @developersp1-9584 ,

Try to upload file into sub folder like this:

 public static void UploadFile(ClientContext context,string uploadFolderUrl, string uploadFilePath)
 {
     var fileCreationInfo = new FileCreationInformation
     {
             Content = System.IO.File.ReadAllBytes(uploadFilePath),
             Overwrite = true,
             Url = Path.GetFileName(uploadFilePath)
     };
     var targetFolder = context.Web.GetFolderByServerRelativeUrl(uploadFolderUrl);
     var uploadFile = targetFolder.Files.Add(fileCreationInfo);
     context.Load(uploadFile);
     context.ExecuteQuery();
 }
    
 using (var ctx = new ClientContext(webUri))
 {
      ctx.Credentials = credentials;
    
      UploadFile(ctx,"LibName/FolderName/Sub Folder Name/Sub Sub Folder Name/Sub Sub Sub Folder Name",filePath);   
 }

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