MsiDatabaseOpenView returns 6 (ERROR_INVALID_HANDLE)

Question

I have a Basic MSI project in InstallShield 2013. I am trying to dynamically insert items in a combobox using an InstallScript custom action. I am currently stuck well before actually inserting the items.

When I try to open the view I get ERROR_INVALID_HANDLE. I would appreciate any advice on what I am missing.

function func(hMSI)
   HWND hDatabase;
   HWND hViewlist;
begin
   hDatabase = MsiGetActiveDatabase(hMSI);
   MsiDatabaseOpenView(hDatabase, "SELECT * FROM `ComboBox` WHERE `Property`='PROP'", hViewList);
end;

MsiDatabaseOpenView keeps returning 6 (ERROR_INVALID_HANDLE) when I use either hDatabase or hMSI as the first parameter.