I've happened to experience when a button does not work for me. Have you tried Objpad while activating a button and/or a link. When I wish to bring it up, I press NVDA plus Control plus tab to walk through the modes it offers. I usually choose the scan mode and position myself on a button and/or a link to try activating it. It sometimes does work, and sometimes does it fail. I also do this. When I cannot activate in the browse mode, I switch to the focus mode to activate. I also try to do one more thing. I switch to the document mode, and then I use the NVDA key with up and down arrows to find what I wish, and when I find it, I hold down the NVDA key, and then I try by hitting enter on it. One more thing you may wish to try. Switch to the browse mode. Find what you wish, and switch to the object review. Hold down the NVDA key and press enter on it. That's what I do. It sometimes helps, and sometimes fails. If you wish to switch between the browsers, try Opera and see what you may experience.