With AWS S3 MultiPart upload to a named directory using C# and the .Net SDK
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The following fails with this error message:
"The specified upload does not exist. The upload ID may be invalid, or the upload may have been aborted or completed."

    UploadPartRequest uploadRequest = new UploadPartRequest()
	.WithBucketName(IniValues.Instance.TargetBucketName)
	.WithKey("junk/20070125.log")
	.WithUploadId(initResponse.UploadId)
	.WithPartNumber(i)
	.WithPartSize(partSize)
	.WithFilePosition(filePosition)
	.WithFilePath("C:\\InetTemp\\Logs\\20070125.log");

The probelm is with the ".WithKey("junk/20070125.log")". If I strip out the "junk/" it works perfectly. 

So the question is, how to upload a file to a specific AWS directory? All the documentation I found shows tha correct way to be to prepend the directory name and a forward slash.  What am I missing?