Remote Management Console not connecting

Hi

i am trying to setup a helpdesk user access into the Sophos Console for the first time and am having a little bother.

The application is installed correctly as matches the installation on my computer exactly and i have no issues.

the error they get when opening is:

Access is denied.

----- [outer exception] -----

   -- error: 0x80070005

   -- facility: Win32

   at class ATL::CComPtr<struct ISMT_CoreServices2> __cdecl bl::CreateCoreServices(const class std::basic_string<wchar_t,struct std::char_traits<wchar_t>,class std::allocator<wchar_t> > &)

   at int __cdecl Run(int,class bl::CommandLine,enum bl::ConsoleType::Type)

   at int __stdcall wWinMain(struct HINSTANCE__ *,struct HINSTANCE__ *,wchar_t *,int)

firewall isn't blocking the connection as same happens even after disabling the firewall on the server.  i have checked the dcom permissions and given the helpdesk group access.

I've confirmed i have given the user access to both the helpdesk role and the sub-estate.

I am not sure what else i am missing that would cause them a problem - and the error above isn't particularly helpful.  Can anyone help at all?

Many thanks