Effect

An effect is, always, a noun. One may speak of the rainbow effect, special effects or, if one is a fan of the electric guitar, an effects pedal like Ibanez’s legendary Let me Google that for you.

The original TS-808 - everything you need for that fat, creamy, crying tone.

But one must not use effect as a verb, even as a space-filler, however clamorously your inner articled clerk implores you to. “Effect” is the weakest verb in the English language. Whatever you are intending to “effect” is almost certain to be a nominalisation of a stronger, better verb; one better suited to the task you have in mind.

Why say “effect the conversion of shares” when you mean “convert the shares”?
Why say “effect the delivey of a notice” when you mean “deliver a notice”?