I've had this problem since i started using TWS a few months ago and it's still frustrating the heck out of me. My option chains never show me anything in the open interest column outside of trading hours although i can see it in graphical representation in my separate open interest window i added. Also sometimes as i click between contract tabs i can briefly see the open interest numbers flash then disappear. I thought maybe a windows or computer issue so i installed on another computer with a clean windows 10 install and got the same thing. I reinstalled new versions of java and again same thing. I tried every version of TWS i could find and no change. Here's another oddity, if i load any Canadian stock i get open interest showing in my options chains making mke think it's a data feed issue. I also do not get any option volume showing on my option scanner on US stocks. My question is does anyone else experience this and how to solve it, is this a TWS bug? Or do i need to subscribe to a data package to get the stuff i am missing. Thanks in advance for any insight here.