Why do I keep getting error messages whenever I install Window's updates on my PC or Laptop? This morning I couldn't open Norton either from the Icon on desktop or from icon in tray. I tried right clicking to do a scan but got a message 'accept terms and conditions'. Clicked yes and nothing happened. Then get an error message 8504 104. Tried restarting but same again. Had to get Norton removal tool and install again. Guess what? Windows had had some updates before I shut down. This keeps happening in W7 and W8 on both machines with various error messages. I then have to waste time removing Norton Internet Security and reinstalling. Is Norton becoming more unstable or is Microsoft deliberately sabotaging Norton Antivirus as it wants us to update to Windows 10 (which I don't want to do until they eliminate current bugs). Extremely frustrated paying for something that is unreliable.