Update page is blank

Just read about Microsoft issuing a recommendation to update your PC immediately, so I went to my Update page. It's blank with just Windows Update at the top and tiny blue dots moving across the very top of the image (you might see them in the attachment). I even did a restart but that didn't help. Norton and Malwarebytes give me a clean bill of health. How do I get the rest of the display back??

Got it corrected. Did a sfc /scannow and it found some corrupted files (see attached). Rebooted and Update window returned to normal.