how to fix "error C2872: 'IDictionary' :ambiguous symbol[ VS2012 - C++/CLI] - c++-cli

Question

I need to use IDictionary in my project. When I add this compiler does not like it and report an obvious error
“error C2872: 'IDictionary' : ambiguous symbol” . However if I create a new sample project compiler never reports any error
Below is the code snippet
Temp.h
#pragma once
#using "System.dll"
using namespace::System;
using namespace::System::Collections;
using namespace::System::Collections::Specialized;
public ref class MyCollection : public NameObjectCollectionBase {
private:
DictionaryEntry^ _de;
// Gets a key-and-value pair (DictionaryEntry) using an index.
public:
property DictionaryEntry^ default[ int ] {
DictionaryEntry^ get(int index) {
_de->Key = this->BaseGetKey( index );
_de->Value = this->BaseGet( index );
return( _de );
}
}
// Adds elements from an IDictionary into the new collection.
MyCollection( IDictionary^ d ) {
_de = gcnew DictionaryEntry();
for each ( DictionaryEntry^ de in d ) {
this->BaseAdd( (String^) de->Key, de->Value );
}
}
// Removes an entry with the specified key from the collection.
void Remove( String^ key ) {
this->BaseRemove( key );
}
// Removes an entry in the specified index from the collection.
void Remove( int index ) {
this->BaseRemoveAt( index );
}
};

Answer 1

Since your application has more that one IDictionary interface in different namespaces you'll have to fully qualify the reference. For example:
System::Collections::IDictionary^ d
Or whatever the namespace of the other IDictionary type is.
Alternatively you could remove the using statements for one of the namespace's.