Bewitched - Season 8 Episode 11
The Warlock in the Gray Flannel Suit

Endoras causing trouble again! This time, instead of breaking up a marriage, shes breaking up Darrins advertising company. She calls up Alonzo, a warlock who casts a spell on Larry, making him like all of his ideas on a carpet account instead of Darrins. It gets to a point that Darrin quits McMann and Tate, but finds out that this is all Endoras fault. To get even with her, Samantha magically sets up an advertising campaign to handle the carpet account.