I also have the same issue. I used to be able to press down E to open object effect rack now i'm unable to. Has anyone found a way around this or has the same issue. Program is up to date and i did an uninstall reinstall still no changes.
The current version is 28.0.1.19. Please always indicate the version that you are working with.
In this version (2020), the Object Effects rack is in the bottom window under the tab Inspector. Simply select an object and click on the Inspector tab if not already open. If you are in, say Loops tab (new in this version) in the bottom window, use the shortcut E and you'll see that it changes to the Inspector tab.