Hi,
 
I tested this and it works, can you post the code you are using which generates the error?
 
 
using System;
using System.Text;
using System.Collections.Generic;
using NetApp.Manage;
namespace NetApp.NMSDK.Example
{
  class ApiClient 
  {
	 static void Main(string[] args)
	 {
		 try
		 {
			NaServer s = new NaServer("<cluster_name>", 1 , 110);
			s.ServerType = NaServer.SERVER_TYPE.FILER;
			s.TransportType = NaServer.TRANSPORT_TYPE.HTTPS;
			s.Port = 443;
			s.Style = NaServer.AUTH_STYLE.LOGIN_PASSWORD;
			s.SetAdminUser("admin", "<password>");
			s.Vserver = "<vserver_name>";
			NaElement api = new NaElement("snapshot-set-reserve");
			api.AddNewChild("percentage","10");
			api.AddNewChild("volume","<volume_name>");
			NaElement xo = s.InvokeElem(api);
			Console.WriteLine(xo.ToPrettyString(""));
		}
		catch (NaAuthException e)
		{
			Console.Error.WriteLine("Authorization Failed: " + e.Message);
		}
		catch (NaApiFailedException e)
		{
			Console.Error.WriteLine("API FAILED: " + e.Message);
		}
		 catch (Exception e)
		{
			Console.Error.WriteLine(e.Message);
		}
	 }
  }
}Have you tried using the "Set-NcSnapshotReserve" cmdlet? EG:
 
PS C:\> import-module dataontap
PS C:\> get-nccommand -api snapshot-set-reserve
Name                                Category        Family               Api
----                                --------        ------               ---
Set-NcSnapshotReserve               snapshot        {vserver}            {snapshot-set-reserve}
PS C:\> get-help Set-NcSnapshotReserve
NAME
    Set-NcSnapshotReserve
SYNOPSIS
    Sets the size of the indicated volume's snapshot reserve to the specified percentage.
SYNTAX
    Set-NcSnapshotReserve [-Volume] <String> [-Percentage] <Int32> [-VserverContext <String>] [-Controller
    <NcController[]>] [-ZapiRetryCount <Int32>] [<CommonParameters>]/Matt
					
				
			
			
				
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