Hello, 

I'm brand new to QuantConnect and this is my first post. I'm going through the tutorial on coding up an EMA cross strategy (youtube link) and have found a weird issue, not sure if it could be a bug. When I run a C# algo for the following parameters:

    security: SPY 
    time period: between 3/20/14 and 3/21/14 
    resolutions: Second, Minute, Hour 

I get an error: 

    "Runtime Error: Microsoft.CSharp.RuntimeBinder.RuntimeBinderException: Cannot perform member binding on `null' value"

This happens with C# and does not happen with Python. 

Here is my C# code:

namespace QuantConnect { public class BasicTemplateAlgorithm : QCAlgorithm { string symbol = "SPY"; public override void Initialize() { SetStartDate(2014, 3, 20); SetEndDate(2014, 3, 21); SetCash(30000); AddEquity(symbol, Resolution.Minute); } public override void OnData(Slice data) { decimal price = data[symbol].Close; } } }

Here is my Python code:

class BasicTemplateAlgorithm(QCAlgorithm): def Initialize(self): self._symbol = "SPY" self.SetStartDate(2014,3,20) self.SetEndDate(2014,3,21) self.SetCash(30000) self.AddEquity(self._symbol, Resolution.Minute) def OnData(self, slice): if slice[self._symbol] is None: return self.lastPrice = slice[self._symbol].Close price = str(self.lastPrice) # self.Debug(price)

Here is the stack trace:

Runtime Error: Microsoft.CSharp.RuntimeBinder.RuntimeBinderException: Cannot perform member binding on `null' value at (wrapper dynamic-method) System.Object:CallSite.Target (System.Runtime.CompilerServices.Closure,System.Runtime.CompilerServices.CallSite,object) at System.Dynamic.UpdateDelegates.UpdateAndExecute1[T0,TRet] (System.Runtime.CompilerServices.CallSite site, T0 arg0) [0x00127] in <63992662b765477a898ef49cdcc99ee2>:0 at (wrapper dynamic-method) System.Object:CallSite.Target (System.Runtime.CompilerServices.Closure,System.Runtime.CompilerServices.CallSite,object) at QuantConnect.BasicTemplateAlgorithm.OnData (QuantConnect.Data.Slice data) [0x00095] in <88556ecddcf344799948cd3cd676333b>:0 at QuantConnect.Lean.Engine.AlgorithmManager.Run (QuantConnect.Packets.AlgorithmNodePacket job, QuantConnect.Interfaces.IAlgorithm algorithm, QuantConnect.Lean.Engine.DataFeeds.IDataFeed feed, QuantConnect.Lean.Engine.TransactionHandlers.ITransactionHandler transactions, QuantConnect.Lean.Engine.Results.IResultHandler results, QuantConnect.Lean.Engine.RealTime.IRealTimeHandler realtime, QuantConnect.Lean.Engine.Server.ILeanManager leanManager, QuantConnect.Lean.Engine.Alpha.IAlphaHandler alphas, System.Threading.CancellationToken token) [0x01258] in <11f348cb016f463b86b03dce3a52e390>:0 (Open Stacktrace)

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