Every once in awhile when I start my computer the little M shield on the task bar is missing.
The larger M shield where the other minimized icons are is there . But when I click on the larger M shield the window does not open ( the one that shows I am protected and by subscription info.
Then little m shied finally appears -----why does it not show up some of time I have no idea what I do or don't do to make it appear
The icon takes a while to appear after startup, the delay depends on your setup but can be a minute or so. You are protected though.
Run the latest version of the Virtual Technician to see if it helps find problems and corrects them: http://mvt.mcafee.com/