How do I cover come on "error C2872: 'IComparer' : ambiguous symbol" error

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C++/CLI

Hi Friends,
Could you please help me to resolve below error.

error C2872: 'IComparer' : ambiguous symbol

My objective is to sort a List.
below is my code :
1) I have a list

 // temp.h
List<smcsequipmentstatusinfo^>^ lsMCSEquipmentStatusInfo;
 So I created a class DeviceGroupComparer inherited from the interface IComparer as shown below

	public ref class DeviceGroupComparer: IComparer<smcsequipmentstatusinfo^>
	{
	public:
		virtual int Compare(SMCSEquipmentStatusInfo^ x, SMCSEquipmentStatusInfo^ y)
		{
			if (x == nullptr)
			{
				if (y == nullptr)
				{  
					return 0;
				}
				else
				{ 
					return -1;
				}
			}
			else
			{
				if (y == nullptr)
				{
					return 1;
				}
				else
				{
					int retval = x->strGroup->CompareTo(y->strGroup);

					if (retval != 0)
					{						
						return retval;
					}
					else
					{
						int retval1 = x->strDeviceNo->CompareTo(y->strDeviceNo);
						if (retval1 != 0)
						{
							return retval1;
						}
						else
						{
							return  x->strDeviceNo->CompareTo(y->strDeviceNo);;
						}						
						return x->strGroup->CompareTo(y->strGroup);
					}
				}
			}
		}
};

// temp. cpp
	DeviceGroupComparer^ DeviceGroup = gcnew DeviceGroupComparer();
        stClientInfo->lsMCSEquipmentStatusInfo->Sort(DeviceGroup);

in temp.cpp ,I just tried to show the way I tried to sort the list.

My observation:
If i select IComparer in "temp.h" and press f12 then in the find symbol result i find these :
interface class System::Collections::Generic::IComparer<t> - c:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.0\mscorlib.dll
interface class System::Collections::IComparer - c:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.0\mscorlib.dll

I am not sure why its pointing to "System::Collections::Generic::IComparer<t>" and "class System::Collections::IComparer"
is it the reason of the error, if so then how can i fix it?