I have the same issue, but it was recently working until the latest update although that might be coincidental. I can use Window Capture, specify the piece of software I need to record but as soon as I click on a drop down area or an icon that would open a pop-up window, naadaa, nothing, just will not work but it use to, did 30 videos in January 2020 just fine. I have told windows in graphics setting OBS. This is not the black screen issue. Yes I'm using a laptop, HP ZBook workstation i7. Tried all sorts of variations to get it back, any suggestions very welcome, I am a relative newbie to OBS. Thanks in advance