I've seen several older post and want to understand what my options are. I have a Dell SR2320L Flat Panel Monitor purchased in 2010. It is now as of about 1 hour ago random pop ups a locked pad lock, blinks for a while and then goes away. What's happened/different?  It's never done this before. What do I need to do (if anything) to stop this from happening?

Thanks ahead of time for any information.