I don't have that problem here.. I'm always able to access the left click start menu from the start button. It doesn't "cease to work" as you describe. Have you used any registry cleaners or optimizers that may have caused the issue? We see such problems when unnecessary optimizers are used as they can frequently delete something they shouldn't.
In the meantime, pressing the "Windows" key on the keyboard should bring up the start menu you're referring to.
Hope this helps.
Grif
After a restart left-clicking on the windows icon displays the Start menu, but later that ceases to work. Then, right-clicking on the windows icon displays a different start menu with no entry for Settings. Does anyone know a quick way to get the left-click to work again without having to restart ? This is not of critical importance since one can get to Settings other ways, e.g. holding the microsoft key down and pressing "i".

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