I've downloaded the latest version of TWS API and ticked the "Enable ActiveX and Sockets Clients" box under API Settings in TWS. However, when attempting to run the sample Excel sheet TwsRtdServer sheet or building simple RTD functions to bring in stock prices I get #N/A error codes. I've tried to repair Excel but the problem still remains. I’m running Excel on Microsoft 365. IB help has told me that it has come to their attention, that MS 365 does not work correctly with RTD. Thus using MS 365 is not recommended for Excel RTD usage. Is this true? Anybody else with similar problem?