Troubles with IntelliSense

Everytime I try to add a new include to either my header or cpp file, it ends up giving me these stupid errors, like **class “UObject” has no member "BeginPlay? **etc. etc.
This happens quite often, and there’s nothing that seems to be wrong with it. I end up putting a space between one of the headers or simply erasing one and adding it back, then BOOM…freaking works. It’s starting to get annoying. What can I do to prevent these stupid errors? Am I just doing something wrong? Even if erase all my includes, back to the auto generated file, it still gives me the same messages