ConfigurationStorage MovieManagerConfiguration; // global variable that holds the settings data

void SettingsDialog::Reload()
{
	mDirectoryList.Clear();
	auto x = MovieManagerConfiguration.SyncDirectories.GetCount(); // this throws the semantics error!
	for (int i = 0; i < x; i++)
	{
		mDirectoryList.Add(MovieManagerConfiguration.SyncDirectories[i]);
	}
}

Inside the constructor of my main window:

mSettingsDialog.WhenSettingsChanged = THISBACK(SettingsChanged);

Inside the open button:

void MovieManager::Options()
{
	mSettingsDialog.Reload();
	mSettingsDialog.Execute();
}

The problem didn't reside in the GetCount() in the above post as you said, the problem resided in my synchroniser:

void MovieSynchroniser::Synchronise(Vector<String> pDirectories)
{
	for (int i = 0; i < pDirectories.GetCount(); i++)
	{
		GetFiles(pDirectories[i]);
	}
}

void MovieSynchroniser::Synchronise(Vector<String>& pDirectories)