@Christof+ I don't know if it pertains since your tool uses the standalone API if I remember correctly but I had to change IB TWS to the Beta version for some reason recently, about 2 months later the gf58ometer quit working. I ultimately figured out that if I switched back to the Stable version all was well. So between Beta and Stable, there is some difference in the IB TWS API, possible whatever change was made there was made to the standalone API as well. IB support was not helpful, they blamed on something else that didn't even sound plausible, figuring it out was just plain luck.