Try this uri:
"https://docs.google.com/feeds/default/private/full/folder%3A" + fRid + "/contents"
// fRid is the resource identifier of the folder .. in your case: 0B2dzFB6YvN-kYTRlNmNhYjEtMTVmNC00ZThkLThiMjQtMzFhZmMzOGE2ZWU1
I also assume that your URI gives this error, because you are using the resource identifier of the as folder - folder: resourceID
Try deleting the folder : and use only RID
Code for cutting "folder:" -
int ridIndex = dRid.IndexOf(":");
Rid = Rid.Substring(ridIndex + 1);
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