diff --git a/Code/Mantid/Framework/Algorithms/src/MuonRemoveExpDecay.cpp b/Code/Mantid/Framework/Algorithms/src/MuonRemoveExpDecay.cpp
index b2a99bda773d04d53f4bfebe1c67179d9fc42b21..f685ad9f31559936fb1aadb6afebc1ea9548b2a0 100644
--- a/Code/Mantid/Framework/Algorithms/src/MuonRemoveExpDecay.cpp
+++ b/Code/Mantid/Framework/Algorithms/src/MuonRemoveExpDecay.cpp
@@ -38,8 +38,7 @@ void MuonRemoveExpDecay::init()
   declareProperty(new API::WorkspaceProperty<API::MatrixWorkspace>("OutputWorkspace", "",
       Direction::Output), "The name of the workspace to be created as the output of the algorithm");
   std::vector<int> empty;
-  declareProperty(new Kernel::ArrayProperty<int>("Spectra", empty, new MandatoryValidator<std::vector<
-      int> > ), "Spectra to remove the exponential decay from");
+  declareProperty(new Kernel::ArrayProperty<int>("Spectra", empty), "Spectra to remove the exponential decay from");
 }
 
 /** Executes the algorithm
diff --git a/Code/Mantid/Framework/Algorithms/test/MuonRemoveExpDecayTest.h b/Code/Mantid/Framework/Algorithms/test/MuonRemoveExpDecayTest.h
index ea1efd54edc46b7ec27ff01cbd95bbc2b3ce2f16..34250a847a564a58ae9dfe7c6535b6e4132f0de3 100644
--- a/Code/Mantid/Framework/Algorithms/test/MuonRemoveExpDecayTest.h
+++ b/Code/Mantid/Framework/Algorithms/test/MuonRemoveExpDecayTest.h
@@ -37,7 +37,6 @@ public:
   void testLoadNexusAndSetProperties()
   {
   //This test does not run on Windows64 as is does not support HDF4 files
-#ifndef _WIN64
 
     loader.initialize();
     loader.setPropertyValue("Filename", "emu00006473.nxs");
@@ -48,21 +47,17 @@ public:
     alg.setPropertyValue("InputWorkspace", "EMU6473");
     alg.setPropertyValue("OutputWorkspace", "Result");
     alg.setPropertyValue("Spectra", "0");
-#endif /*_WIN64*/
   }
 
   void testProperties()
   {
     //This test does not run on Windows64 as is does not support HDF4 files
-#ifndef _WIN64
     TS_ASSERT_EQUALS( alg.getPropertyValue("Spectra"), "0");
-#endif /*_WIN64*/
   }
 
   void testExecute()
   {
       //This test does not run on Windows64 as is does not support HDF4 files
-#ifndef _WIN64
     try 
     {
       TS_ASSERT_EQUALS(alg.execute(),true);
@@ -73,9 +68,29 @@ public:
     }
 
     Workspace_const_sptr outputWS = AnalysisDataService::Instance().retrieve("Result");
-#endif /*_WIN64*/
   }
 
+  void testWhereOptional3rdArgNotSet()
+  {
+  //This test does not run on Windows64 as is does not support HDF4 files
+
+    MuonRemoveExpDecay alg2;
+    alg2.initialize();
+
+    alg2.setPropertyValue("InputWorkspace", "EMU6473");
+    alg2.setPropertyValue("OutputWorkspace", "MuonRemoveExpDecayResult");
+
+    try 
+    {
+      TS_ASSERT_EQUALS(alg2.execute(),true);
+    }
+    catch(std::runtime_error e)
+    {
+      TS_FAIL(e.what());
+    }
+  }
+
+
 private:
   MuonRemoveExpDecay alg;
   Mantid::NeXus::LoadMuonNexus loader;