Bazinga,
А вот и подоспел ответ от ADN DevHelp:
Dear Alexander Rivilis,
Thanks for contacting ADN support.
From the error, it seems that the code is trying to check out a file which is not the tip version.
So in your code instead of the below line:
File file = connection.WebServiceManager.DocumentService.GetFilesByMasterId(_need).First();
Try using:
File file = connection.WebServiceManager.DocumentService.GetLatestFileByMasterId(_need);
Hope this helps. Do let me know if it doesn't.
Т.е. именно тоже самое решение...